Update iOS Runner project version

Update Chinese translation

.github/workflows/build-artifacts.yml

@@ -12,7 +12,7 @@ permissions:
   id-token: write
 
 env:
-  FLUTTER_VERSION: "3.35.6"
+  FLUTTER_VERSION: "3.41.4"
   APP_NAME: meshcore-sar
   ANDROID_NDK_VERSION: "27.0.12077973"
 
@@ -280,7 +280,7 @@ jobs:
         run: flutter pub get
 
       - name: Build web release
-        run: flutter build web --release --base-href /meshcore_sar_app/
+        run: flutter build web --release --base-href /meshcore-sar/
 
       - name: Upload pages artifact
         uses: actions/upload-pages-artifact@v3

.github/workflows/build-multiplatform.yml

@@ -10,7 +10,7 @@ on:
   workflow_dispatch:
 
 env:
-  FLUTTER_VERSION: '3.35.6'
+  FLUTTER_VERSION: '3.41.4'
 
 jobs:
   analyze:

README.md

@@ -16,7 +16,7 @@
 
 MeshCore SAR helps teams coordinate in low-connectivity or no-connectivity environments with messaging, voice, images, maps, and live location context in one app.
 It uses the MeshCore protocol over LoRa for long-range, infrastructure-free communication.
-`iOS TestFlight:` https://testflight.apple.com/join/HhzerdHp
+`iOS TestFlight:` https://testflight.apple.com/join/nCZYMPPz
 
 ## Highlights
 

android/app/src/main/AndroidManifest.xml

@@ -23,6 +23,7 @@
 
     <!-- Microphone for voice messages -->
     <uses-permission android:name="android.permission.RECORD_AUDIO" />
+    <uses-permission android:name="android.permission.CAMERA" />
 
     <!-- Notifications -->
     <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />

docs/image-mode-technical.md

@@ -2,23 +2,28 @@
 
 ## 1. Overview
 
-Image mode mirrors the voice on-demand architecture exactly:
+Image mode mirrors the voice on-demand architecture exactly, including
+swarm-assisted recovery for stalled partial transfers:
 
 - **Control plane (text messages):**
-  - `IE1:` image envelope announces image availability in chat.
-  - `IR1:` direct fetch request asks sender to stream image fragments.
+  - `IE4:` image envelope announces image availability in chat.
+- **Control plane (raw binary request):**
+  - Binary image fetch request (same raw route as image fragments).
 - **Data plane (raw binary packets):**
   - `ImagePacket` binary payload streamed via `cmdSendRawData` / `pushRawData`.
 
 Images are never broadcast in full to channels.  Chat carries only metadata;
 pixels are fetched on demand when the user taps the image bubble.
 
+Shared swarm fallback is documented in
+[Swarm Mode Technical Design](./swarm-mode-technical.md).
+
 ## 2. Key Modules
 
 - `lib/utils/image_message_parser.dart`
   - `ImagePacket` (binary fragment format)
-  - `ImageEnvelope` (`IE1`)
-  - `ImageFetchRequest` (`IR1`)
+  - `ImageEnvelope` (`IE4`)
+  - `ImageFetchRequest` (binary)
   - `fragmentImage()` — split compressed bytes into packets
   - `reassembleImage()` — join received fragments into bytes
 - `lib/screens/messages_tab.dart`
@@ -26,8 +31,9 @@ pixels are fetched on demand when the user taps the image bubble.
 - `lib/providers/image_provider.dart`
   - Reassembly sessions, outgoing cache, deferred serving
   - Outgoing sessions also registered as complete incoming sessions for immediate local display
+  - Received partial sessions can be re-served during swarm recovery
 - `lib/providers/app_provider.dart`
-  - Incoming routing for `IE1`, `IR1`, binary `0x49` packets
+  - Incoming routing for `IE4`, binary image fetch requests, binary `0x49` packets, and raw swarm control payloads
 - `lib/widgets/messages/image_message_bubble.dart`
   - Square cover thumbnail (up to 256 px); tap-to-load for received images;
     progress ring during fetch; full-screen `InteractiveViewer` on tap
@@ -39,65 +45,64 @@ pixels are fetched on demand when the user taps the image bubble.
 
 ## 3. Wire Formats
 
-### 3.1 Image Envelope (`IE1`)
+### 3.1 Image Envelope (`IE4`)
 
-Prefix: `IE1:` + colon-delimited payload
+Prefix: `IE4:` + colon-delimited compact payload (base36 numeric fields)
 
 Fields:
 
 | Field        | Type   | Description                                    |
 |--------------|--------|------------------------------------------------|
-| `sid`        | string | 8 hex chars (4 bytes), session ID              |
-| `fmt`        | int    | `ImageFormat.id` (0 = AVIF, 1 = JPEG)         |
-| `total`      | int    | Fragment count (1..255)                        |
-| `w`          | int    | Actual image width after compression (pixels)  |
-| `h`          | int    | Actual image height after compression (pixels) |
-| `bytes`      | int    | Total compressed size in bytes                 |
-| `senderKey6` | string | 12 hex chars (6 bytes sender prefix)           |
-| `ts`         | int    | Unix timestamp (seconds)                       |
-| `ver`        | int    | Protocol version (currently `1`)               |
-
+| `sid`        | string | base36 token for 32-bit session ID             |
+| `fmt`        | base36 | `ImageFormat.id` (0 = AVIF, 1 = JPEG)         |
+| `total`      | base36 | Fragment count (1..255)                        |
+| `w`          | base36 | Actual image width after compression (pixels)  |
+| `h`          | base36 | Actual image height after compression (pixels) |
+| `bytes`      | base36 | Total compressed size in bytes                 |
 Compact format:
 
 ```text
-IE1:{sid}:{fmt}:{total}:{w}:{h}:{bytes}:{senderKey6}:{ts}:{ver}
+IE4:{sid}:{fmt}:{total}:{w}:{h}:{bytes}
 ```
 
 Example (256×171 landscape image, 14 fragments):
 
 ```text
-IE1:deadbeef:0:14:256:171:2100:aabbccddeeff:1700000000:1
+IE4:a:0:e:74:4r:1mc
 ```
 
-Note: `w` and `h` reflect the actual post-compression dimensions, which preserve
+Note: `sid` is base36 on wire and expands to 8-hex internally.
+`w` and `h` reflect the actual post-compression dimensions, which preserve
 the source aspect ratio (contain within the configured max size).
 
-### 3.2 Image Fetch Request (`IR1`)
+### 3.2 Image Fetch Request (`IR4` + binary)
 
-Same structure as `VR1`:
+Text format:
 
 ```text
-IR1:{sid}:{want}:{requesterKey6}:{ts}:{ver}
+IR4:{sid}:{want}:{requesterKey6}
+```
+
+Binary payload format:
+
+```text
+[magic=0x69][sid:4B][flags:1B][requesterKey6:6B][missingCount:1B][missingIndices...]
 ```
 
 | Field            | Value                    |
 |------------------|--------------------------|
-| `want`           | `a` (= "all fragments")  |
-| `requesterKey6`  | 12 hex chars             |
-| `ver`            | `1`                      |
-
+| `flags`          | bit0=1 => request missing indices, else all |
+| `requesterKey6`  | 6-byte requester key prefix |
 ### 3.3 Raw Image Packet (data plane)
 
 Binary payload structure:
 
 - Byte 0: magic `0x49` (`'I'`)
 - Bytes 1..4: session ID (4 bytes)
-- Byte 5: format ID
-- Byte 6: fragment index (0-based)
-- Byte 7: total fragments
-- Bytes 8..N: image data (max 152 bytes per fragment)
+- Byte 5: fragment index (0-based)
+- Bytes 6..N: image data (max 152 bytes per fragment)
 
-Header is 8 bytes — identical layout to `VoicePacket`.
+Header is 6 bytes. Image format and total fragment count come from the `IE4` envelope.
 
 ## 4. Compression Pipeline
 
@@ -151,24 +156,34 @@ only the shorter axis is padded — no cropping occurs.
 7. Envelope sent via normal message path:
    - Channel: `sendChannelMessage`
    - Direct: `sendTextMessage`
-8. Local placeholder message added (`IE1:` text, `deliveryStatus.sending`).
+8. Local placeholder message added (`IE4:` text, `deliveryStatus.sending`).
 
 ## 6. Incoming Flow (Receive)
 
-### 6.1 `IE1` envelope received
+### 6.1 `IE4` envelope received
 
 `AppProvider` calls `imageProvider.registerEnvelope()` and adds the message to
 chat.  The bubble shows a grey square placeholder with a download icon.
 
-### 6.2 `IR1` request received
+### 6.2 Binary image fetch request received
 
 `AppProvider` treats it as control-plane only (not added to chat):
 
-- Validates requester key prefix.
 - Resolves requester contact.
 - Calls `imageProvider.serveSessionTo()` which streams all cached fragments.
 
-### 6.3 Raw packet received (`pushRawData`, magic `0x49`)
+### 6.3 Swarm control messages received
+
+`AppProvider` also handles shared raw swarm discovery payloads:
+
+- binary swarm requests advertise which image fragments are still missing
+- binary swarm availability responses advertise which fragments another peer can relay
+- swarm payloads arrive via `pushRawData` and are intercepted instead of being added to chat
+
+Shared discovery and responder semantics are documented in
+[Swarm Mode Technical Design](./swarm-mode-technical.md).
+
+### 6.4 Raw packet received (`pushRawData`, magic `0x49`)
 
 `AppProvider.onRawDataReceived` parses `ImagePacket` binary and calls
 `imageProvider.addFragment()`.  When the session becomes complete, the bubble
@@ -187,6 +202,9 @@ When `cacheOutgoingSession()` is called it also writes all fragments into
 `_sessions[sessionId]`, so the sender sees the image immediately in the bubble
 (no tap-to-load required for own messages).
 
+If a peer later receives only part of an image session, those received fragments
+can also be served onward to another requester during swarm recovery.
+
 ## 8. Display
 
 `ImageMessageBubble` (max width 256 px):
@@ -194,7 +212,8 @@ When `cacheOutgoingSession()` is called it also writes all fragments into
 - **Complete session**: `AspectRatio(1.0)` → `AvifImage.memory(fit: cover)`
   square thumbnail; tap → full-screen `InteractiveViewer` with fade transition.
 - **Incomplete/missing**: grey square placeholder with download icon;
-  tap → sends `IR1` fetch request.
+  tap → sends binary fetch request, with raw swarm fallback if the original
+  sender path stalls.
 - **Loading**: circular progress indicator showing `received/total` count.
 - **Error**: broken-image icon.
 
@@ -212,11 +231,12 @@ Image bubbles and Message Technical Details show an **estimated transmit time**
 The estimate is airtime-based (LoRa packet model), not just compressed image size:
 
 - Source inputs:
-  - `total` fragments and `bytes` from `IE1` envelope
+  - `total` fragments and `bytes` from `IE4` envelope
+  - all numeric envelope values are decoded from base36
   - `pathLen` from message metadata
   - current radio params from `deviceInfo`: `radioBw`, `radioSf`, `radioCr`
 - Per-fragment payload model:
-  - `meshHeader(2)` + `pathLen` + `imageHeader(8)` + `fragmentBytes`
+  - `meshHeader(2)` + `pathLen` + `imageHeader(6)` + `fragmentBytes`
 - LoRa airtime:
   - standard symbol-time formula (preamble + payload symbols)
 - Mesh pacing/hops:
@@ -244,11 +264,45 @@ Fallback defaults are used when radio params are unavailable: `SF10`, `BW250kHz`
 ## 11. Operational Constraints
 
 - No firmware changes required (reuses `cmdSendRawData` / `pushRawData`).
-- On-demand fetch works only if sender app is online and has cached session.
+- On-demand fetch prefers the original sender, but a partial image can also be
+  completed from alternate peers that already hold matching fragments.
 - Raw return path requires a valid direct route to requester.
 - Available on iOS and Android (`image_picker` + `flutter_avif`).
+- Swarm discovery uses the same `cmdSendRawData` / `pushRawData` path as image
+  fetch and fragment delivery.
 
-## 12. High-Level Sequence
+### 11.1 Raw Binary Routing Semantics
+
+- Image fragment payloads use companion command `CMD_SEND_RAW_DATA` (`25` / `0x19`).
+- Companion push back to the app is `PUSH_CODE_RAW_DATA` (`0x84`).
+- Over-the-air packet type for this flow is `PAYLOAD_TYPE_RAW_CUSTOM` (`0x0F`).
+- This flow is direct-route only, not flood/broadcast:
+  - it is sent to one destination path;
+  - only nodes on that path relay it;
+  - it is **not** received by everyone in the mesh.
+
+## 12. Swarm Fallback Sequence
+
+```mermaid
+sequenceDiagram
+  participant A as Original Sender
+  participant P as Peer With Fragments
+  participant N as Reachable Peers
+  participant B as Receiver App
+
+  A->>M: Send IE4 envelope
+  M->>B: Deliver IE4
+  B->>A: Direct binary image fetch request
+  A->>B: Stream raw ImagePacket fragments (partial)
+  Note over A,B: Sender path stops responding
+  B->>N: Raw swarm requests with missing image fragment indices
+  P->>B: Raw swarm availability response
+  B->>P: Direct binary fetch request for missing subset
+  P->>B: Stream remaining raw ImagePacket fragments
+  B->>B: Reassemble completed image
+```
+
+## 13. High-Level Sequence
 
 ```mermaid
 sequenceDiagram
@@ -260,10 +314,10 @@ sequenceDiagram
   A->>A: Compress: contain resize → grayscale → PNG → AVIF
   A->>A: Fragment into ≤152B packets
   A->>A: Cache outgoing + populate local session (immediate display)
-  A->>M: Send IE1 envelope (actual w×h, fragment count)
-  M->>B: Deliver IE1
+  A->>M: Send IE4 envelope (actual w×h, fragment count)
+  M->>B: Deliver IE4
   B->>B: Render grey placeholder bubble
-  B->>A: Tap → send IR1 fetch request
+  B->>A: Tap → send binary fetch request
   A->>B: Stream binary ImagePackets
   B->>B: Reassemble fragments
   B->>B: Display AVIF image (cover thumbnail)

docs/swarm-mode-technical.md

@@ -0,0 +1,148 @@
+# Swarm Mode Technical Design
+
+## 1. Overview
+
+Swarm mode is a shared media-recovery transport used by both voice and image
+sessions when the original sender path stops responding after some fragments
+have already propagated through the mesh.
+
+It adds a lightweight **swarm discovery plane** on top of the existing
+**direct raw-data transfer plane**:
+
+- **Discovery plane (raw custom control payloads):**
+  - `MediaSwarmRequest`
+  - `MediaSwarmAvailability`
+- **Transfer plane (direct raw binary):**
+  - existing `VoiceFetchRequest` / `ImageFetchRequest`
+  - existing `VoicePacket` / `ImagePacket`
+
+Swarm mode does not broadcast media payloads. It fans out raw control requests
+to reachable peers, collects raw availability responses, and then fetches media
+from the best responder.
+
+## 2. Problem It Solves
+
+Without swarm mode, media fetch is limited to the original sender's direct raw
+path. If that sender goes offline, moves, or stops responding, a receiver can
+be left with a partial session even when other peers already hold useful
+fragments.
+
+Swarm mode lets the receiver discover alternate peers and fetch the missing
+subset directly from them.
+
+## 3. Control Messages
+
+### 3.1 Media Swarm Request (binary)
+
+```text
+[magic=0x6d][kind=0x01][mediaType:1B][sessionId:4B][requesterKey6:6B][missingCount:1B][missingIndices...]
+```
+
+Fields:
+
+- `mediaType` — `voice` or `image`
+- `sessionId` — 8 hex chars
+- `requesterKey6` — 12 hex chars identifying the requesting device
+- `missingCount` — `0` means the requester needs all fragments
+- `missingIndices` — exact missing fragment indices when `missingCount > 0`
+
+Example:
+
+```text
+6d 01 02 de ad be ef aa bb cc dd ee ff 03 00 02 09
+```
+
+### 3.2 Media Swarm Availability (binary)
+
+```text
+[magic=0x6d][kind=0x02][mediaType:1B][sessionId:4B][requesterKey6:6B][responderKey6:6B][availableCount:1B][availableIndices...]
+```
+
+Fields:
+
+- `mediaType` — `voice` or `image`
+- `sessionId` — 8 hex chars
+- `requesterKey6` — copied from the swarm request
+- `responderKey6` — 12 hex chars identifying the responding peer
+- `availableCount` — `0` means the responder can satisfy the full request
+- `availableIndices` — exact fragment indices held when `availableCount > 0`
+
+Example:
+
+```text
+6d 02 02 de ad be ef aa bb cc dd ee ff 11 22 33 44 55 66 02 02 09
+```
+
+## 4. Requester Behavior
+
+When a voice or image session is incomplete:
+
+1. Prefer the original sender if its direct raw route is healthy.
+2. If the original sender path is unavailable or not responding, send a raw
+   swarm request to reachable peers with the exact missing fragment indices.
+3. Wait up to **10 seconds** for raw availability responses.
+4. Rank responders by overlap with the current missing set.
+5. Skip the original sender when choosing alternate peers.
+6. Send a direct binary fetch request to the best responder for only the
+   missing subset that responder advertised.
+
+Actual media transfer uses the same `cmdSendRawData` / `pushRawData` path as the
+swarm control messages.
+
+## 5. Responder Behavior
+
+A peer that receives a swarm request:
+
+- checks whether it has fragments for the requested media session
+- replies only if it has at least one requested fragment
+- advertises only fragments it actually holds
+- may reply from:
+  - its outgoing cache, or
+  - a partially/fully received incoming session
+
+This enables torrent-like relay behavior without requiring the peer to be the
+original sender.
+
+## 6. Visibility and Routing
+
+- Swarm control payloads are carried by `cmdSendRawData` and received through
+  `pushRawData`.
+- They are intercepted by the app and **must not be surfaced in chat**.
+- Discovery is a direct raw fan-out to reachable peers, not a public-channel
+  broadcast.
+- Media packets themselves remain direct-route raw packets.
+
+## 7. Constraints
+
+- No firmware changes are required.
+- Swarm mode only helps if at least one peer has already received some useful
+  fragments.
+- Peers can only relay fragments they actually have.
+- Alternate peers still need a valid direct raw route back to the requester.
+- Swarm mode improves recovery from sender-path failure, but it does not change
+  the underlying raw-packet size, airtime, or hop constraints.
+
+## 8. High-Level Sequence
+
+```mermaid
+sequenceDiagram
+  participant S as Original Sender
+  participant P as Peer With Fragments
+  participant N as Reachable Peers
+  participant R as Requester
+
+  S->>R: Direct raw fragments (partial)
+  Note over S,R: Original sender path stops responding
+  R->>N: Raw swarm requests with exact missing fragments
+  P->>R: Raw swarm availability response
+  R->>P: Direct binary fetch request for missing subset
+  P->>R: Direct raw fragments
+  R->>R: Reassemble completed session
+```
+
+## 9. Integration Points
+
+- Voice-specific behavior is summarized in `docs/voice-mode-technical.md`.
+- Image-specific behavior is summarized in `docs/image-mode-technical.md`.
+- This document is the shared source of truth for swarm discovery and fallback
+  semantics.

docs/voice-mode-technical.md

@@ -2,87 +2,74 @@
 
 ## 1. Overview
 
-Voice mode uses a **two-plane architecture**:
+Voice mode uses a **two-plane architecture** with optional swarm-assisted
+recovery:
 
 - **Control plane (text messages):**
-  - `VE1:` voice envelope announces voice availability in chat.
-  - `VR1:` direct fetch request asks sender to stream voice payload.
+  - `VE3:` voice envelope announces voice availability in chat.
+- **Control plane (raw binary request):**
+  - Binary voice fetch request (same raw route as voice packets).
 - **Data plane (raw binary packets):**
   - `VoicePacket` payload streamed via `cmdSendRawData` and received through `pushRawData`.
 
 This design avoids broadcasting full voice payloads to channels/rooms. Chat carries only metadata; audio is fetched on demand when user presses play.
 
+Swarm fallback is documented in [Swarm Mode Technical Design](./swarm-mode-technical.md).
+
 ## 2. Key Modules
 
 - `lib/utils/voice_message_parser.dart`
-  - `VoicePacket` (legacy text + binary packet format)
-  - `VoiceEnvelope` (`VE1`)
-  - `VoiceFetchRequest` (`VR1`)
+  - `VoicePacket` (binary direct-packet format)
+  - `VoiceEnvelope` (`VE3`)
+  - `VoiceFetchRequest` (binary)
 - `lib/screens/messages_tab.dart`
   - Capture/encode voice, cache encoded packets, send envelope only
 - `lib/providers/voice_provider.dart`
   - Reassembly/playback sessions
   - Outgoing session cache + deferred serving
 - `lib/providers/app_provider.dart`
-  - Incoming routing for `VE1` and `VR1`
+  - Incoming routing for `VE3`, binary voice fetch requests, and raw swarm control payloads
   - Handles raw packet ingestion
 - `lib/widgets/messages/voice_message_bubble.dart`
   - Play behavior (immediate play if complete, otherwise fetch + auto-play)
 - `lib/providers/messages_provider.dart`
-  - Message-level voice detection (`VE1` + legacy `V:`)
+  - Message-level voice detection (`VE3`)
 - `lib/services/message_storage_service.dart`
   - Persists `isVoice` and `voiceId`
 
 ## 3. Wire Formats
 
-### 3.1 Voice Envelope (`VE1`)
+### 3.1 Voice Envelope (`VE3`)
 
-Prefix: `VE1:` + colon-delimited compact payload
+Prefix: `VE3:` + colon-delimited compact payload (base36 numeric fields)
 
 Fields:
 
-- `sid` (string, 8 hex chars): session ID
-- `mode` (int): codec mode ID (`VoicePacketMode.id`)
-- `total` (int): packet count (1..255)
-- `durMs` (int): estimated duration in ms
-- `senderKey6` (string, 12 hex chars): sender public-key prefix (6 bytes)
-- `ts` (int): unix timestamp seconds
-- `ver` (int): protocol version (currently `1`)
+- `sid` (string): base36 token for 32-bit session ID
+- `mode` (base36): codec mode ID (`VoicePacketMode.id`)
+- `total` (base36): packet count (1..255)
+- `durS` (base36): estimated duration in seconds
+
+`sid` is base36 on wire and expands to 8-hex internally.
 
 Compact format:
 
 ```text
-VE1:{sid}:{mode}:{total}:{durMs}:{senderKey6}:{ts}:{ver}
+VE3:{sid}:{mode}:{total}:{durS}
 ```
 
 Example:
 
 ```text
-VE1:deadbeef:1:4:3200:aabbccddeeff:1700000000:1
+VE3:a:1:4:4
 ```
 
-### 3.2 Voice Fetch Request (`VR1`)
+### 3.2 Voice Fetch Request (binary)
 
-Prefix: `VR1:` + colon-delimited compact payload
-
-Fields:
-
-- `sid` (string, 8 hex chars): requested session
-- `want` (string): currently `a` (compact token for `all`)
-- `requesterKey6` (string, 12 hex chars): requester key prefix
-- `ts` (int): unix timestamp seconds
-- `ver` (int): protocol version (`1`)
-
-Compact format:
+Binary payload format:
 
 ```text
-VR1:{sid}:{want}:{requesterKey6}:{ts}:{ver}
-```
-
-Example:
-
-```text
-VR1:deadbeef:a:112233445566:1700000010:1
+[magic=0x72][sid:4B][flags:1B][requesterKey6:6B][missingCount:1B][missingIndices...]
 ```
 
 ### 3.3 Raw Voice Packet (data plane)
@@ -91,10 +78,10 @@ Binary payload structure:
 
 - Byte 0: magic `0x56` (`'V'`)
 - Bytes 1..4: session ID (4 bytes)
-- Byte 5: mode ID
-- Byte 6: packet index
-- Byte 7: total packets
-- Bytes 8..N: codec2 data
+- Byte 5: packet index
+- Bytes 6..N: codec2 data
+
+Header is 6 bytes. Mode and total packet count come from the `VE3` envelope.
 
 ## 4. Outgoing Flow (Send)
 
@@ -102,27 +89,38 @@ Binary payload structure:
 2. Each chunk is codec2-encoded into `VoicePacket` objects.
 3. Packets are cached in `VoiceProvider` outgoing cache (TTL 15 min).
 4. Sender inserts local voice placeholder message (`isVoice=true`, `voiceId=sessionId`).
-5. Sender sends one envelope (`VE1`) through normal message path:
+5. Sender sends one envelope (`VE3`) through normal message path:
    - channel/room: `sendChannelMessage`
    - direct: `sendTextMessage`
 6. **No raw audio packets are sent during initial send.**
 
 ## 5. Incoming Routing
 
-### 5.1 `VE1` envelope received
+### 5.1 `VE3` envelope received
 
-`AppProvider` marks message as voice (`isVoice`, `voiceId`) and adds it to chat.
+`AppProvider` records sender identity from message metadata, registers the voice
+session envelope, marks the message as voice (`isVoice`, `voiceId`), and adds it to chat.
 
-### 5.2 `VR1` request received
+### 5.2 Binary voice fetch request received
 
 `AppProvider` treats it as control-plane only:
 
 - request is not added to chat
-- validates requester prefix match against sender metadata
 - resolves requester contact via key prefix
 - calls `voiceProvider.serveSessionTo(...)`
 
-### 5.3 Raw packet received (`pushRawData`)
+### 5.3 Swarm control messages received
+
+`AppProvider` also handles raw swarm control payloads:
+
+- binary swarm requests advertise which voice fragments are still missing
+- binary swarm availability responses advertise which fragments a peer can relay
+- swarm control payloads arrive via `pushRawData` and are not added to chat history
+
+Swarm semantics are shared with image mode and documented in
+[Swarm Mode Technical Design](./swarm-mode-technical.md).
+
+### 5.4 Raw packet received (`pushRawData`)
 
 `AppProvider.onRawDataReceived` parses `VoicePacket` binary and appends to session in `VoiceProvider`.
 
@@ -132,10 +130,15 @@ In `VoiceMessageBubble`:
 
 - If session already complete: play immediately.
 - If incomplete/missing:
-  1. Resolve sender contact (message sender prefix or `VE1.senderKey6` fallback)
-  2. Send direct `VR1` fetch request
-  3. Show requesting state in UI
-  4. Auto-play when session becomes complete
+  1. Resolve sender contact from message sender metadata
+  2. Prefer a direct fetch from the original sender if its raw route is healthy
+  3. If the sender path does not respond, fan out a raw swarm request with the
+     exact missing packet indices to reachable peers
+  4. Wait up to 10 seconds for raw peer availability responses
+  5. Send a direct binary fetch request to the best alternate peer for the
+     missing subset it advertised
+  6. Show requesting state in UI
+  7. Auto-play when session becomes complete
 
 If sender cannot be resolved or request cannot be sent, bubble remains and shows: **"Voice unavailable right now"**.
 
@@ -150,10 +153,13 @@ If sender cannot be resolved or request cannot be sent, bubble remains and shows
 
 Serving prerequisites:
 
-- session exists in cache
+- session exists in outgoing cache or already-received session state
 - `sendRawPacketCallback` configured
 - requester has direct path (`outPathLen >= 0`)
 
+Received partial sessions can therefore act as relay sources during swarm
+recovery.
+
 ## 8. Persistence
 
 `MessageStorageService` now stores and restores:
@@ -170,10 +176,9 @@ Parser validation enforces:
 - strict hex lengths for IDs and key prefixes
 - valid mode range
 - valid packet counts and duration bounds
-- fixed protocol version (`ver == 1`)
-- `VR1.want` token `a` (internally normalized to `all`)
-
-`VR1` handling verifies sender prefix matches `requesterKey6` to reduce spoofing risk.
+- compact base36 numeric fields in envelope/request
+- Binary request flags specify `all` or `missing` indices.
+- Request payload includes `requesterKey6` to resolve return route.
 
 ## 10. Transmit Time Estimate (UI)
 
@@ -182,12 +187,13 @@ Voice bubbles and Message Technical Details show an **estimated transmit time**
 The estimate is airtime-based (LoRa packet model), not file-duration-only:
 
 - Source inputs:
-  - `packetCount` and `durationMs` from `VE1` envelope, or
+  - `packetCount` and `durationMs` from `VE3` envelope, or
+  - numeric envelope values decoded from base36
   - actual received `VoicePacket.codec2Data.length` bytes when local session packets exist
   - `pathLen` from message metadata
   - current radio params from `deviceInfo`: `radioBw`, `radioSf`, `radioCr`
 - Per-packet payload model:
-  - `meshHeader(2)` + `pathLen` + `voiceHeader(8)` + `codec2Bytes`
+  - `meshHeader(2)` + `pathLen` + `voiceHeader(6)` + `codec2Bytes`
 - LoRa airtime:
   - standard symbol-time formula (preamble + payload symbols)
 - Mesh pacing/hops:
@@ -206,30 +212,44 @@ Fallback defaults are used when radio params are unavailable: `SF10`, `BW250kHz`
 ## 11. Operational Constraints
 
 - No firmware changes required.
-- On-demand fetch works only if sender app is online and has cached session.
+- On-demand fetch prefers the original sender, but a partial session can also be
+  completed from alternate peers that already hold packets.
 - Raw return path needs a currently valid direct route to requester.
 - Voice capture is available on iOS and Android (`Platform.isIOS || Platform.isAndroid`).
+- Swarm discovery uses the same `cmdSendRawData` / `pushRawData` path as voice
+  fetch and packet delivery.
 
-## 12. Backward Compatibility
+### 11.1 Raw Binary Routing Semantics
 
-- Legacy `V:` text packet parsing is still supported.
-- Message voice detection accepts both new `VE1` and legacy `V:` formats.
+- Voice payload packets use companion command `CMD_SEND_RAW_DATA` (`25` / `0x19`).
+- Companion push back to the app is `PUSH_CODE_RAW_DATA` (`0x84`).
+- Over-the-air packet type for this flow is `PAYLOAD_TYPE_RAW_CUSTOM` (`0x0F`).
+- This flow is direct-route only, not flood/broadcast:
+  - it is sent to one destination path;
+  - only nodes on that path relay it;
+  - it is **not** received by everyone in the mesh.
 
-## 13. High-Level Sequence
+## 12. High-Level Sequence
 
 ```mermaid
 sequenceDiagram
   participant A as Sender App
-  participant M as Mesh Chat
+  participant P as Peer With Packets
+  participant N as Reachable Peers
   participant B as Receiver App
 
   A->>A: Record + encode voice packets
   A->>A: Cache session packets (TTL 15m)
-  A->>M: Send VE1 envelope
-  M->>B: Deliver VE1
+  A->>M: Send VE3 envelope
+  M->>B: Deliver VE3
   B->>B: Render voice bubble (metadata only)
-  B->>A: Send VR1 request on Play
-  A->>B: Stream raw VoicePacket packets
+  B->>A: Send binary fetch request on Play
+  A->>B: Stream raw VoicePacket packets (partial)
+  Note over A,B: Sender path stops responding
+  B->>N: Raw swarm requests with missing voice packet indices
+  P->>B: Raw swarm availability response
+  B->>P: Direct binary fetch request for missing subset
+  P->>B: Stream remaining raw VoicePacket packets
   B->>B: Reassemble session
   B->>B: Auto-play when complete
 ```

ios/Podfile

@@ -39,5 +39,13 @@ end
 post_install do |installer|
   installer.pods_project.targets.each do |target|
     flutter_additional_ios_build_settings(target)
+    # codec2_flutter uses ARM-specific register asm("sp") in debug_alloc.h that
+    # fails to compile for iOS simulators. Voice codec support is only required
+    # on real iOS devices, so skip the native Codec2 sources for simulator SDKs.
+    if target.name == 'codec2_flutter'
+      target.build_configurations.each do |config|
+        config.build_settings['EXCLUDED_SOURCE_FILE_NAMES[sdk=iphonesimulator*]'] = '*.c *.cpp'
+      end
+    end
   end
 end

ios/Podfile.lock

@@ -59,12 +59,11 @@ PODS:
     - Flutter
   - nsd_ios (0.0.1):
     - Flutter
-  - ObjectBox (4.4.1)
-  - objectbox_flutter_libs (0.0.1):
-    - Flutter
-    - ObjectBox (= 4.4.1)
   - package_info_plus (0.4.5):
     - Flutter
+  - path_provider_foundation (0.0.1):
+    - Flutter
+    - FlutterMacOS
   - permission_handler_apple (9.3.0):
     - Flutter
   - record_ios (1.2.0):
@@ -100,8 +99,8 @@ DEPENDENCIES:
   - geolocator_apple (from `.symlinks/plugins/geolocator_apple/darwin`)
   - image_picker_ios (from `.symlinks/plugins/image_picker_ios/ios`)
   - nsd_ios (from `.symlinks/plugins/nsd_ios/ios`)
-  - objectbox_flutter_libs (from `.symlinks/plugins/objectbox_flutter_libs/ios`)
   - package_info_plus (from `.symlinks/plugins/package_info_plus/ios`)
+  - path_provider_foundation (from `.symlinks/plugins/path_provider_foundation/darwin`)
   - permission_handler_apple (from `.symlinks/plugins/permission_handler_apple/ios`)
   - record_ios (from `.symlinks/plugins/record_ios/ios`)
   - share_plus (from `.symlinks/plugins/share_plus/ios`)
@@ -114,7 +113,6 @@ SPEC REPOS:
   trunk:
     - DKImagePickerController
     - DKPhotoGallery
-    - ObjectBox
     - SDWebImage
     - SwiftyGif
 
@@ -145,10 +143,10 @@ EXTERNAL SOURCES:
     :path: ".symlinks/plugins/image_picker_ios/ios"
   nsd_ios:
     :path: ".symlinks/plugins/nsd_ios/ios"
-  objectbox_flutter_libs:
-    :path: ".symlinks/plugins/objectbox_flutter_libs/ios"
   package_info_plus:
     :path: ".symlinks/plugins/package_info_plus/ios"
+  path_provider_foundation:
+    :path: ".symlinks/plugins/path_provider_foundation/darwin"
   permission_handler_apple:
     :path: ".symlinks/plugins/permission_handler_apple/ios"
   record_ios:
@@ -165,7 +163,7 @@ EXTERNAL SOURCES:
     :path: ".symlinks/plugins/vibration/ios"
 
 SPEC CHECKSUMS:
-  audioplayers_darwin: 4f9ca89d92d3d21cec7ec580e78ca888e5fb68bd
+  audioplayers_darwin: 835ced6edd4c9fc8ebb0a7cc9e294a91d99917d5
   codec2_flutter: 15e24fa897d9d903a2afb1cc5a17ae3ac88b6d6f
   device_info_plus: 21fcca2080fbcd348be798aa36c3e5ed849eefbe
   DKImagePickerController: 946cec48c7873164274ecc4624d19e3da4c1ef3c
@@ -176,13 +174,12 @@ SPEC CHECKSUMS:
   flutter_background_service_ios: 00d31bdff7b4bfe06d32375df358abe0329cf87e
   flutter_blue_plus_darwin: 20a08bfeaa0f7804d524858d3d8744bcc1b6dbc3
   flutter_compass: b236ab69b61545cce89fd58527f401a7587d5cc1
-  flutter_local_notifications: a5a732f069baa862e728d839dd2ebb904737effb
+  flutter_local_notifications: 643a3eda1ce1c0599413ca31672536d423dee214
   geolocator_apple: ab36aa0e8b7d7a2d7639b3b4e48308394e8cef5e
   image_picker_ios: e0ece4aa2a75771a7de3fa735d26d90817041326
   nsd_ios: 596ad79109ddd3e52d665f650f36428049e3653e
-  ObjectBox: 7da4aceb5013d041bfafdbc6d744a26918b09757
-  objectbox_flutter_libs: 09b1dec1b4cd27bf1a5f9bae7ccaa7e43588bf31
   package_info_plus: af8e2ca6888548050f16fa2f1938db7b5a5df499
+  path_provider_foundation: bb55f6dbba17d0dccd6737fe6f7f34fbd0376880
   permission_handler_apple: 4ed2196e43d0651e8ff7ca3483a069d469701f2d
   record_ios: 412daca2350b228e698fffcd08f1f94ceb1e3844
   SDWebImage: e9fc87c1aab89a8ab1bbd74eba378c6f53be8abf
@@ -193,6 +190,6 @@ SPEC CHECKSUMS:
   url_launcher_ios: 7a95fa5b60cc718a708b8f2966718e93db0cef1b
   vibration: ca8104a8875b9c493e15b21b04e456befd0ff6eb
 
-PODFILE CHECKSUM: 3c63482e143d1b91d2d2560aee9fb04ecc74ac7e
+PODFILE CHECKSUM: 2d56c9747241a29800bf539d978b210bda037878
 
 COCOAPODS: 1.16.2

ios/Runner.xcodeproj/project.pbxproj

@@ -489,7 +489,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
-				CURRENT_PROJECT_VERSION = 74;
+				CURRENT_PROJECT_VERSION = 111;
 				DEVELOPMENT_TEAM = JND55328G8;
 				ENABLE_BITCODE = NO;
 				INFOPLIST_FILE = Runner/Info.plist;
@@ -511,7 +511,7 @@
 			buildSettings = {
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 74;
+				CURRENT_PROJECT_VERSION = 111;
 				DEVELOPMENT_TEAM = JND55328G8;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
@@ -530,7 +530,7 @@
 			buildSettings = {
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 74;
+				CURRENT_PROJECT_VERSION = 111;
 				DEVELOPMENT_TEAM = JND55328G8;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
@@ -547,7 +547,7 @@
 			buildSettings = {
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 74;
+				CURRENT_PROJECT_VERSION = 111;
 				DEVELOPMENT_TEAM = JND55328G8;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
@@ -679,7 +679,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
-				CURRENT_PROJECT_VERSION = 74;
+				CURRENT_PROJECT_VERSION = 111;
 				DEVELOPMENT_TEAM = JND55328G8;
 				ENABLE_BITCODE = NO;
 				INFOPLIST_FILE = Runner/Info.plist;
@@ -702,7 +702,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
-				CURRENT_PROJECT_VERSION = 74;
+				CURRENT_PROJECT_VERSION = 111;
 				DEVELOPMENT_TEAM = JND55328G8;
 				ENABLE_BITCODE = NO;
 				INFOPLIST_FILE = Runner/Info.plist;

ios/Runner/AppDelegate.swift

@@ -1,5 +1,6 @@
 import UIKit
 import Flutter
+import UserNotifications
 
 @main
 @objc class AppDelegate: FlutterAppDelegate {
@@ -8,6 +9,7 @@ import Flutter
     didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
   ) -> Bool {
     GeneratedPluginRegistrant.register(with: self)
+    UNUserNotificationCenter.current().delegate = self as UNUserNotificationCenterDelegate
     return super.application(application, didFinishLaunchingWithOptions: launchOptions)
   }
 }

ios/Runner/Info.plist

@@ -43,9 +43,11 @@
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
-	<string>74</string>
+	<string>111</string>
 	<key>LSRequiresIPhoneOS</key>
 	<true/>
+	<key>ITSAppUsesNonExemptEncryption</key>
+	<false/>
 	<key>NSBluetoothAlwaysUsageDescription</key>
 	<string>MeshCore SAR needs Bluetooth to communicate with MeshCore devices for Search &amp; Rescue operations</string>
 	<key>NSBluetoothPeripheralUsageDescription</key>
@@ -100,6 +102,7 @@
 	<key>UIBackgroundModes</key>
 	<array>
 		<string>location</string>
+		<string>bluetooth-central</string>
 		<string>bluetooth-peripheral</string>
 	</array>
 	<key>UILaunchStoryboardName</key>

ios/fastlane/report.xml

@@ -5,22 +5,22 @@
     
     
       
-      <testcase classname="fastlane.lanes" name="0: default_platform" time="0.000195">
+      <testcase classname="fastlane.lanes" name="0: default_platform" time="0.000256">
         
       </testcase>
     
       
-      <testcase classname="fastlane.lanes" name="1: increment_build_number" time="0.405396">
+      <testcase classname="fastlane.lanes" name="1: increment_build_number" time="0.924905">
         
       </testcase>
     
       
-      <testcase classname="fastlane.lanes" name="2: build_app" time="101.387002">
+      <testcase classname="fastlane.lanes" name="2: build_app" time="113.366384">
         
       </testcase>
     
       
-      <testcase classname="fastlane.lanes" name="3: upload_to_app_store" time="209.873722">
+      <testcase classname="fastlane.lanes" name="3: upload_to_app_store" time="755.542625">
         
       </testcase>
     

lib/l10n/app_ru.arb

@@ -0,0 +1,567 @@
+{
+  "@@locale": "ru",
+  "appTitle": "MeshCore SAR",
+  "messages": "Сообщения",
+  "contacts": "Контакты",
+  "map": "Карта",
+  "settings": "Настройки",
+  "connect": "Подключить",
+  "disconnect": "Отключить",
+  "noDevicesFound": "Устройства не найдены",
+  "scanAgain": "Повторить поиск",
+  "tapToConnect": "Нажмите для подключения",
+  "deviceNotConnected": "Устройство не подключено",
+  "locationPermissionDenied": "Доступ к геолокации запрещён",
+  "locationPermissionPermanentlyDenied": "Доступ к геолокации запрещён навсегда. Включите его в настройках.",
+  "locationPermissionRequired": "Доступ к геолокации необходим для GPS-трекинга и координации команды. Вы можете включить его позже в настройках.",
+  "locationServicesDisabled": "Службы геолокации отключены. Пожалуйста, включите их в настройках.",
+  "failedToGetGpsLocation": "Не удалось получить GPS-координаты",
+  "failedToAdvertise": "Ошибка трансляции: {error}",
+  "cancelReconnection": "Отменить переподключение",
+  "general": "Основные",
+  "theme": "Тема",
+  "chooseTheme": "Выбрать тему",
+  "light": "Светлая",
+  "dark": "Тёмная",
+  "blueLightTheme": "Синяя светлая тема",
+  "blueDarkTheme": "Синяя тёмная тема",
+  "sarRed": "SAR Красная",
+  "alertEmergencyMode": "Режим тревоги / ЧС",
+  "sarGreen": "SAR Зелёная",
+  "safeAllClearMode": "Режим «Всё в порядке»",
+  "autoSystem": "Авто (Система)",
+  "followSystemTheme": "Следовать системной теме",
+  "showRxTxIndicators": "Показывать индикаторы RX/TX",
+  "displayPacketActivity": "Отображать активность пакетов в верхней панели",
+  "disableMap": "Отключить карту",
+  "disableMapDescription": "Скрыть вкладку карты для экономии заряда батареи",
+  "language": "Язык",
+  "chooseLanguage": "Выбрать язык",
+  "save": "Сохранить",
+  "cancel": "Отмена",
+  "close": "Закрыть",
+  "about": "О приложении",
+  "appVersion": "Версия приложения",
+  "appName": "Название приложения",
+  "aboutMeshCoreSar": "О MeshCore SAR",
+  "aboutDescription": "Приложение для поисково-спасательных операций, разработанное для аварийно-спасательных служб. Возможности:\n\n• BLE mesh-сеть для связи между устройствами\n• Офлайн-карты с несколькими вариантами слоёв\n• Отслеживание членов команды в реальном времени\n• Тактические маркеры SAR (найденный человек, пожар, место сбора)\n• Управление контактами и обмен сообщениями\n• GPS-трекинг с показанием курса компаса\n• Кэширование тайлов карт для работы офлайн",
+  "technologiesUsed": "Используемые технологии:",
+  "technologiesList": "• Flutter для кросс-платформенной разработки\n• BLE (Bluetooth Low Energy) для mesh-сети\n• OpenStreetMap для карт\n• Provider для управления состоянием\n• SharedPreferences для локального хранилища",
+  "moreInfo": "Подробнее",
+  "packageName": "Имя пакета",
+  "sampleData": "Тестовые данные",
+  "sampleDataDescription": "Загрузить или очистить тестовые контакты, сообщения каналов и маркеры SAR",
+  "loadSampleData": "Загрузить тестовые данные",
+  "clearAllData": "Очистить все данные",
+  "clearAllDataConfirmTitle": "Очистить все данные",
+  "clearAllDataConfirmMessage": "Это удалит все контакты и маркеры SAR. Вы уверены?",
+  "clear": "Очистить",
+  "loadedSampleData": "Загружено: {teamCount} членов команды, {channelCount} каналов, {sarCount} маркеров SAR, {messageCount} сообщений",
+  "failedToLoadSampleData": "Не удалось загрузить тестовые данные: {error}",
+  "allDataCleared": "Все данные очищены",
+  "failedToStartBackgroundTracking": "Не удалось запустить фоновое отслеживание. Проверьте разрешения и BLE-соединение.",
+  "locationBroadcast": "Трансляция геолокации: {latitude}, {longitude}",
+  "defaultPinInfo": "PIN-код по умолчанию для устройств без экрана — 123456. Проблемы с сопряжением? Удалите устройство из Bluetooth в системных настройках.",
+  "noMessagesYet": "Сообщений пока нет",
+  "pullDownToSync": "Потяните вниз для синхронизации сообщений",
+  "deleteContact": "Удалить контакт",
+  "delete": "Удалить",
+  "viewOnMap": "Показать на карте",
+  "refresh": "Обновить",
+  "resetPath": "Сбросить маршрут (перепроложить)",
+  "publicKeyCopied": "Публичный ключ скопирован в буфер обмена",
+  "copiedToClipboard": "{label} скопировано в буфер обмена",
+  "pleaseEnterPassword": "Пожалуйста, введите пароль",
+  "failedToSyncContacts": "Не удалось синхронизировать контакты: {error}",
+  "loggedInSuccessfully": "Вход выполнен! Ожидание сообщений комнаты...",
+  "loginFailed": "Ошибка входа — неверный пароль",
+  "loggingIn": "Вход в {roomName}...",
+  "failedToSendLogin": "Не удалось отправить данные входа: {error}",
+  "lowLocationAccuracy": "Низкая точность геолокации",
+  "continue_": "Продолжить",
+  "sendSarMarker": "Отправить маркер SAR",
+  "deleteDrawing": "Удалить рисунок",
+  "drawingTools": "Инструменты рисования",
+  "drawLine": "Нарисовать линию",
+  "drawLineDesc": "Нарисуйте произвольную линию на карте",
+  "drawRectangle": "Нарисовать прямоугольник",
+  "drawRectangleDesc": "Нарисуйте прямоугольную область на карте",
+  "measureDistance": "Измерить расстояние",
+  "measureDistanceDesc": "Долгое нажатие на две точки для измерения",
+  "clearMeasurement": "Сбросить измерение",
+  "distanceLabel": "Расстояние: {distance}",
+  "longPressForSecondPoint": "Долгое нажатие для второй точки",
+  "longPressToStartMeasurement": "Долгое нажатие для установки первой точки",
+  "longPressToStartNewMeasurement": "Долгое нажатие для начала нового измерения",
+  "shareDrawings": "Поделиться рисунками",
+  "clearAllDrawings": "Удалить все рисунки",
+  "completeLine": "Завершить линию",
+  "broadcastDrawingsToTeam": "Транслировать {count} рисун{plural} команде",
+  "removeAllDrawings": "Удалить все {count} рисун{plural}",
+  "deleteAllDrawingsConfirm": "Удалить все {count} рисун{plural} с карты?",
+  "drawing": "Рисунок",
+  "shareDrawingsCount": "Поделиться {count} рисун{plural}",
+  "showReceivedDrawings": "Показать полученные рисунки",
+  "showingAllDrawings": "Показаны все рисунки",
+  "showingOnlyYourDrawings": "Показаны только ваши рисунки",
+  "showSarMarkers": "Показать маркеры SAR",
+  "showingSarMarkers": "Маркеры SAR отображаются",
+  "hidingSarMarkers": "Маркеры SAR скрыты",
+  "clearAll": "Очистить всё",
+  "publicChannel": "Публичный канал",
+  "broadcastToAll": "Трансляция всем ближайшим узлам (временно)",
+  "storedPermanently": "Сохранено постоянно в комнате",
+  "notConnectedToDevice": "Устройство не подключено",
+  "typeYourMessage": "Введите сообщение...",
+  "quickLocationMarker": "Быстрый маркер местоположения",
+  "markerType": "Тип маркера",
+  "sendTo": "Отправить в",
+  "noDestinationsAvailable": "Нет доступных получателей.",
+  "selectDestination": "Выберите получателя...",
+  "ephemeralBroadcastInfo": "Временно: передаётся по эфиру. Не сохраняется — узлы должны быть онлайн.",
+  "persistentRoomInfo": "Постоянно: хранится неизменно в комнате. Синхронизируется автоматически и доступно офлайн.",
+  "location": "Местоположение",
+  "fromMap": "С карты",
+  "gettingLocation": "Получение местоположения...",
+  "locationError": "Ошибка геолокации",
+  "retry": "Повторить",
+  "refreshLocation": "Обновить местоположение",
+  "accuracyMeters": "Точность: ±{accuracy}м",
+  "notesOptional": "Заметки (необязательно)",
+  "addAdditionalInformation": "Добавьте дополнительную информацию...",
+  "lowAccuracyWarning": "Точность геолокации: ±{accuracy}м. Этого может быть недостаточно для операций SAR.\n\nПродолжить всё равно?",
+  "loginToRoom": "Войти в комнату",
+  "enterPasswordInfo": "Введите пароль для доступа к этой комнате. Пароль будет сохранён для дальнейшего использования.",
+  "password": "Пароль",
+  "enterRoomPassword": "Введите пароль комнаты",
+  "loggingInDots": "Вход...",
+  "login": "Войти",
+  "failedToAddRoom": "Не удалось добавить комнату на устройство: {error}\n\nВозможно, комната ещё не объявила себя.\nПопробуйте подождать, пока комната не выйдет на связь.",
+  "direct": "Напрямую",
+  "flood": "Широковещательно",
+  "loggedIn": "Вход выполнен",
+  "noGpsData": "Нет данных GPS",
+  "distance": "Расстояние",
+  "directPingTimeout": "Таймаут прямого пинга — повтор {name} широковещательно...",
+  "pingFailed": "Пинг не удался: {name} — ответ не получен",
+  "deleteContactConfirmation": "Вы уверены, что хотите удалить \"{name}\"?\n\nЭто удалит контакт как из приложения, так и с сопряжённого радиоустройства.",
+  "failedToRemoveContact": "Не удалось удалить контакт: {error}",
+  "type": "Тип",
+  "publicKey": "Публичный ключ",
+  "lastSeen": "Последнее появление",
+  "roomStatus": "Статус комнаты",
+  "loginStatus": "Статус входа",
+  "notLoggedIn": "Не выполнен вход",
+  "adminAccess": "Доступ администратора",
+  "yes": "Да",
+  "no": "Нет",
+  "permissions": "Разрешения",
+  "passwordSaved": "Пароль сохранён",
+  "locationColon": "Местоположение:",
+  "telemetry": "Телеметрия",
+  "voltage": "Напряжение",
+  "battery": "Батарея",
+  "temperature": "Температура",
+  "humidity": "Влажность",
+  "pressure": "Давление",
+  "gpsTelemetry": "GPS (телеметрия)",
+  "updated": "Обновлено",
+  "pathResetInfo": "Маршрут сброшен для {name}. Следующее сообщение найдёт новый путь.",
+  "reLoginToRoom": "Войти в комнату повторно",
+  "heading": "Курс",
+  "elevation": "Высота",
+  "accuracy": "Точность",
+  "bearing": "Азимут",
+  "direction": "Направление",
+  "filterMarkers": "Фильтр маркеров",
+  "filterMarkersTooltip": "Фильтровать маркеры",
+  "contactsFilter": "Контакты",
+  "repeatersFilter": "Ретрансляторы",
+  "sarMarkers": "Маркеры SAR",
+  "foundPerson": "Найденный человек",
+  "fire": "Пожар",
+  "stagingArea": "Место сбора",
+  "showAll": "Показать все",
+  "locationUnavailable": "Местоположение недоступно",
+  "ahead": "впереди",
+  "degreesRight": "{degrees}° вправо",
+  "degreesLeft": "{degrees}° влево",
+  "latLonFormat": "Ш: {latitude} Д: {longitude}",
+  "noContactsYet": "Контактов пока нет",
+  "connectToDeviceToLoadContacts": "Подключите устройство для загрузки контактов",
+  "teamMembers": "Члены команды",
+  "repeaters": "Ретрансляторы",
+  "rooms": "Комнаты",
+  "channels": "Каналы",
+  "selectMapLayer": "Выбрать слой карты",
+  "openStreetMap": "OpenStreetMap",
+  "openTopoMap": "OpenTopoMap",
+  "esriSatellite": "ESRI Спутник",
+  "googleHybrid": "Google Гибрид",
+  "googleRoadmap": "Google Дороги",
+  "googleTerrain": "Google Рельеф",
+  "dragToPosition": "Перетащите для позиционирования",
+  "createSarMarker": "Создать маркер SAR",
+  "compass": "Компас",
+  "navigationAndContacts": "Навигация и контакты",
+  "sarAlert": "ТРЕВОГА SAR",
+  "textCopiedToClipboard": "Текст скопирован в буфер обмена",
+  "cannotReplySenderMissing": "Не удаётся ответить: нет информации об отправителе",
+  "cannotReplyContactNotFound": "Не удаётся ответить: контакт не найден",
+  "copyText": "Копировать текст",
+  "saveAsTemplate": "Сохранить как шаблон",
+  "templateSaved": "Шаблон успешно сохранён",
+  "templateAlreadyExists": "Шаблон с таким эмодзи уже существует",
+  "deleteMessage": "Удалить сообщение",
+  "deleteMessageConfirmation": "Вы уверены, что хотите удалить это сообщение?",
+  "shareLocation": "Поделиться местоположением",
+  "shareLocationText": "{markerInfo}\n\nКоординаты: {lat}, {lon}\n\nGoogle Maps: {url}",
+  "sarLocationShare": "Местоположение SAR",
+  "justNow": "Только что",
+  "minutesAgo": "{minutes}м назад",
+  "hoursAgo": "{hours}ч назад",
+  "daysAgo": "{days}д назад",
+  "secondsAgo": "{seconds}с назад",
+  "sending": "Отправка...",
+  "sent": "Отправлено",
+  "delivered": "Доставлено",
+  "deliveredWithTime": "Доставлено ({time}мс)",
+  "failed": "Ошибка",
+  "broadcast": "Трансляция",
+  "deliveredToContacts": "Доставлено {delivered}/{total} контактам",
+  "allDelivered": "Все доставлено",
+  "recipientDetails": "Детали получателей",
+  "pending": "Ожидание",
+  "sarMarkerFoundPerson": "Найденный человек",
+  "sarMarkerFire": "Место пожара",
+  "sarMarkerStagingArea": "Место сбора",
+  "sarMarkerObject": "Найденный объект",
+  "from": "От",
+  "coordinates": "Координаты",
+  "tapToViewOnMap": "Нажмите, чтобы открыть на карте",
+  "radioSettings": "Настройки радио",
+  "frequencyMHz": "Частота (МГц)",
+  "frequencyExample": "например, 869.618",
+  "bandwidth": "Полоса пропускания",
+  "spreadingFactor": "Коэффициент расширения",
+  "codingRate": "Скорость кодирования",
+  "txPowerDbm": "Мощность TX (дБм)",
+  "maxPowerDbm": "Макс: {power} дБм",
+  "you": "Вы",
+  "exportFailed": "Ошибка экспорта: {error}",
+  "importFailed": "Ошибка импорта: {error}",
+  "unknown": "Неизвестно",
+  "onlineLayers": "Онлайн-слои",
+  "locationTrail": "Трек местоположения",
+  "showTrailOnMap": "Показать трек на карте",
+  "trailVisible": "Трек отображается на карте",
+  "trailHiddenRecording": "Трек скрыт (запись продолжается)",
+  "duration": "Продолжительность",
+  "points": "Точки",
+  "clearTrail": "Очистить трек",
+  "clearTrailQuestion": "Очистить трек?",
+  "clearTrailConfirmation": "Вы уверены, что хотите очистить текущий трек? Это действие нельзя отменить.",
+  "noTrailRecorded": "Трек ещё не записан",
+  "startTrackingToRecord": "Запустите отслеживание геолокации для записи трека",
+  "trailControls": "Управление треком",
+  "contactTrails": "Треки контактов",
+  "showAllContactTrails": "Показать все треки контактов",
+  "noContactsWithLocationHistory": "Нет контактов с историей местоположения",
+  "showingTrailsForContacts": "Показаны треки для {count} контактов",
+  "individualContactTrails": "Индивидуальные треки контактов",
+  "deviceInformation": "Информация об устройстве",
+  "bleName": "Имя BLE",
+  "meshName": "Имя в сети Mesh",
+  "notSet": "Не задано",
+  "model": "Модель",
+  "version": "Версия",
+  "buildDate": "Дата сборки",
+  "firmware": "Прошивка",
+  "maxContacts": "Макс. контактов",
+  "maxChannels": "Макс. каналов",
+  "publicInfo": "Публичная информация",
+  "meshNetworkName": "Название сети Mesh",
+  "nameBroadcastInMesh": "Имя, транслируемое в mesh-объявлениях",
+  "telemetryAndLocationSharing": "Телеметрия и передача местоположения",
+  "lat": "Ш",
+  "lon": "Д",
+  "useCurrentLocation": "Использовать текущее местоположение",
+  "noneUnknown": "Нет/Неизвестно",
+  "chatNode": "Узел чата",
+  "repeater": "Ретранслятор",
+  "roomChannel": "Комната/Канал",
+  "typeNumber": "Тип {number}",
+  "copiedToClipboardShort": "{label} скопировано в буфер обмена",
+  "failedToSave": "Не удалось сохранить: {error}",
+  "failedToGetLocation": "Не удалось получить местоположение: {error}",
+  "sarTemplates": "Шаблоны SAR",
+  "manageSarTemplates": "Управление шаблонами целеуказания",
+  "addTemplate": "Добавить шаблон",
+  "editTemplate": "Изменить шаблон",
+  "deleteTemplate": "Удалить шаблон",
+  "templateName": "Название шаблона",
+  "templateNameHint": "например, Найденный человек",
+  "templateEmoji": "Эмодзи",
+  "emojiRequired": "Требуется эмодзи",
+  "nameRequired": "Требуется название",
+  "templateDescription": "Описание (необязательно)",
+  "templateDescriptionHint": "Добавьте дополнительный контекст...",
+  "templateColor": "Цвет",
+  "previewFormat": "Предпросмотр (формат сообщения SAR)",
+  "importFromClipboard": "Импорт",
+  "exportToClipboard": "Экспорт",
+  "deleteTemplateConfirmation": "Удалить шаблон '{name}'?",
+  "templateAdded": "Шаблон добавлен",
+  "templateUpdated": "Шаблон обновлён",
+  "templateDeleted": "Шаблон удалён",
+  "templatesImported": "{count, plural, =0{Шаблоны не импортированы} =1{Импортирован 1 шаблон} other{Импортировано {count} шаблонов}}",
+  "templatesExported": "{count, plural, =1{1 шаблон экспортирован в буфер обмена} other{{count} шаблонов экспортировано в буфер обмена}}",
+  "resetToDefaults": "Сбросить до умолчаний",
+  "resetToDefaultsConfirmation": "Все пользовательские шаблоны будут удалены и восстановлены 4 шаблона по умолчанию. Продолжить?",
+  "reset": "Сбросить",
+  "resetComplete": "Шаблоны сброшены до умолчаний",
+  "noTemplates": "Шаблоны недоступны",
+  "tapAddToCreate": "Нажмите +, чтобы создать первый шаблон",
+  "ok": "ОК",
+  "permissionsSection": "Разрешения",
+  "locationPermission": "Разрешение геолокации",
+  "checking": "Проверка...",
+  "locationPermissionGrantedAlways": "Разрешено (всегда)",
+  "locationPermissionGrantedWhileInUse": "Разрешено (при использовании)",
+  "locationPermissionDeniedTapToRequest": "Запрещено — нажмите для запроса",
+  "locationPermissionPermanentlyDeniedOpenSettings": "Запрещено навсегда — откройте настройки",
+  "locationPermissionDialogContent": "Доступ к геолокации запрещён навсегда. Включите его в настройках устройства для GPS-трекинга и обмена местоположением.",
+  "openSettings": "Открыть настройки",
+  "locationPermissionGranted": "Разрешение геолокации получено!",
+  "locationPermissionRequiredForGps": "Разрешение геолокации необходимо для GPS-трекинга и обмена местоположением.",
+  "locationPermissionAlreadyGranted": "Разрешение геолокации уже предоставлено.",
+  "sarNavyBlue": "SAR Тёмно-синяя",
+  "sarNavyBlueDescription": "Профессиональный / оперативный режим",
+  "selectRecipient": "Выбрать получателя",
+  "broadcastToAllNearby": "Трансляция всем ближайшим",
+  "searchRecipients": "Поиск получателей...",
+  "noContactsFound": "Контакты не найдены",
+  "noRoomsFound": "Комнаты не найдены",
+  "noRecipientsAvailable": "Нет доступных получателей",
+  "noChannelsFound": "Каналы не найдены",
+  "newMessage": "Новое сообщение",
+  "channel": "Канал",
+  "samplePoliceLead": "Руководитель группы полиции",
+  "sampleDroneOperator": "Оператор дрона",
+  "sampleFirefighterAlpha": "Пожарный",
+  "sampleMedicCharlie": "Медик",
+  "sampleCommandDelta": "Командование",
+  "sampleFireEngine": "Пожарная машина",
+  "sampleAirSupport": "Авиационная поддержка",
+  "sampleBaseCoordinator": "Базовый координатор",
+  "channelEmergency": "Аварийный",
+  "channelCoordination": "Координация",
+  "channelUpdates": "Обновления",
+  "sampleTeamMember": "Тестовый член команды",
+  "sampleScout": "Тестовый разведчик",
+  "sampleBase": "Тестовая база",
+  "sampleSearcher": "Тестовый поисковик",
+  "sampleObjectBackpack": " Найден рюкзак синего цвета",
+  "sampleObjectVehicle": " Брошенный автомобиль — установить владельца",
+  "sampleObjectCamping": " Обнаружено туристическое снаряжение",
+  "sampleObjectTrailMarker": " Указатель тропы найден вне маршрута",
+  "sampleMsgAllTeamsCheckIn": "Всем группам: сообщить о готовности",
+  "sampleMsgWeatherUpdate": "Погода: ясно, температура 18°C",
+  "sampleMsgBaseCamp": "Базовый лагерь развёрнут у места сбора",
+  "sampleMsgTeamAlpha": "Группа выдвигается в сектор 2",
+  "sampleMsgRadioCheck": "Проверка связи — всем станциям ответить",
+  "sampleMsgWaterSupply": "Вода доступна на контрольной точке 3",
+  "sampleMsgTeamBravo": "Группа докладывает: сектор 1 чист",
+  "sampleMsgEtaRallyPoint": "Прибытие на место сбора: 15 минут",
+  "sampleMsgSupplyDrop": "Сброс снаряжения подтверждён на 14:00",
+  "sampleMsgDroneSurvey": "Разведка дроном завершена — ничего не обнаружено",
+  "sampleMsgTeamCharlie": "Группа запрашивает подкрепление",
+  "sampleMsgRadioDiscipline": "Всем подразделениям: соблюдать радиодисциплину",
+  "sampleMsgUrgentMedical": "СРОЧНО: нужна медицинская помощь в секторе 4",
+  "sampleMsgAdultMale": " Взрослый мужчина, в сознании",
+  "sampleMsgFireSpotted": "Обнаружен пожар — координаты следуют",
+  "sampleMsgSpreadingRapidly": " Распространяется быстро!",
+  "sampleMsgPriorityHelicopter": "ПРИОРИТЕТ: нужна поддержка вертолёта",
+  "sampleMsgMedicalTeamEnRoute": "Медицинская группа движется к вашему местоположению",
+  "sampleMsgEvacHelicopter": "Вертолёт эвакуации: прибытие через 10 минут",
+  "sampleMsgEmergencyResolved": "Чрезвычайная ситуация ликвидирована — опасности нет",
+  "sampleMsgEmergencyStagingArea": " Аварийное место сбора",
+  "sampleMsgEmergencyServices": "Аварийные службы уведомлены и реагируют",
+  "sampleAlphaTeamLead": "Руководитель группы",
+  "sampleBravoScout": "Разведчик",
+  "sampleCharlieMedic": "Медик",
+  "sampleDeltaNavigator": "Навигатор",
+  "sampleEchoSupport": "Поддержка",
+  "sampleBaseCommand": "Базовое командование",
+  "sampleFieldCoordinator": "Полевой координатор",
+  "sampleMedicalTeam": "Медицинская группа",
+  "mapDrawing": "Рисунок на карте",
+  "navigateToDrawing": "Перейти к рисунку",
+  "copyCoordinates": "Копировать координаты",
+  "hideFromMap": "Скрыть с карты",
+  "lineDrawing": "Линия",
+  "rectangleDrawing": "Прямоугольник",
+  "manualCoordinates": "Ввод координат вручную",
+  "enterCoordinatesManually": "Ввести координаты вручную",
+  "latitudeLabel": "Широта",
+  "longitudeLabel": "Долгота",
+  "exampleCoordinates": "Пример: 55.7558, 37.6173",
+  "shareDrawing": "Поделиться рисунком",
+  "shareWithAllNearbyDevices": "Поделиться со всеми ближайшими устройствами",
+  "shareToRoom": "Отправить в комнату",
+  "sendToPersistentStorage": "Отправить в постоянное хранилище комнаты",
+  "deleteDrawingConfirm": "Вы уверены, что хотите удалить этот рисунок?",
+  "drawingDeleted": "Рисунок удалён",
+  "yourDrawingsCount": "Ваши рисунки ({count})",
+  "shared": "Передано",
+  "line": "Линия",
+  "rectangle": "Прямоугольник",
+  "updateAvailable": "Доступно обновление",
+  "currentVersion": "Текущая",
+  "latestVersion": "Последняя",
+  "downloadUpdate": "Скачать",
+  "updateLater": "Позже",
+  "cadastralParcels": "Кадастровые участки",
+  "forestRoads": "Лесные дороги",
+  "wmsOverlays": "WMS-наложения",
+  "hikingTrails": "Туристические маршруты",
+  "mainRoads": "Главные дороги",
+  "houseNumbers": "Номера домов",
+  "fireHazardZones": "Пожароопасные зоны",
+  "historicalFires": "Исторические пожары",
+  "firebreaks": "Противопожарные просеки",
+  "krasFireZones": "Пожарные зоны Краса",
+  "placeNames": "Названия мест",
+  "municipalityBorders": "Границы муниципалитетов",
+  "topographicMap": "Топографическая карта 1:25000",
+  "recentMessages": "Последние сообщения",
+  "addChannel": "Добавить канал",
+  "channelName": "Название канала",
+  "channelNameHint": "например, Группа спасения Альфа",
+  "channelSecret": "Секрет канала",
+  "channelSecretHint": "Общий пароль для этого канала",
+  "channelSecretHelp": "Этот секрет необходимо передать всем членам команды, которым нужен доступ к каналу",
+  "channelTypesInfo": "Hash-каналы (#команда): секрет генерируется из названия автоматически. Одно название = один канал на всех устройствах.\n\nЗакрытые каналы: используется явный секрет. Войти могут только те, у кого есть секрет.",
+  "hashChannelInfo": "Hash-канал: секрет будет автоматически создан из названия. Все, кто использует одно и то же имя, окажутся в одном канале.",
+  "channelNameRequired": "Требуется название канала",
+  "channelNameTooLong": "Название канала не должно превышать 31 символ",
+  "channelSecretRequired": "Требуется секрет канала",
+  "channelSecretTooLong": "Секрет канала не должен превышать 32 символа",
+  "invalidAsciiCharacters": "Разрешены только символы ASCII",
+  "channelCreatedSuccessfully": "Канал успешно создан",
+  "channelCreationFailed": "Не удалось создать канал: {error}",
+  "deleteChannel": "Удалить канал",
+  "deleteChannelConfirmation": "Вы уверены, что хотите удалить канал \"{channelName}\"? Это действие нельзя отменить.",
+  "channelDeletedSuccessfully": "Канал успешно удалён",
+  "channelDeletionFailed": "Не удалось удалить канал: {error}",
+  "createChannel": "Создать канал",
+  "wizardBack": "Назад",
+  "wizardSkip": "Пропустить",
+  "wizardNext": "Далее",
+  "wizardGetStarted": "Начать",
+  "wizardWelcomeTitle": "Добро пожаловать в MeshCore SAR",
+  "wizardWelcomeDescription": "Мощный инструмент связи вне сети для поисково-спасательных операций. Поддерживайте связь с командой через mesh-радио, когда традиционные сети недоступны.",
+  "wizardConnectingTitle": "Подключение к радиоустройству",
+  "wizardConnectingDescription": "Подключите смартфон к радиоустройству MeshCore по Bluetooth для связи вне сети.",
+  "wizardConnectingFeature1": "Поиск ближайших устройств MeshCore",
+  "wizardConnectingFeature2": "Сопряжение с радиоустройством по Bluetooth",
+  "wizardConnectingFeature3": "Работает полностью офлайн — интернет не нужен",
+  "wizardChannelTitle": "Каналы",
+  "wizardChannelDescription": "Транслируйте сообщения всем участникам канала — идеально для общих объявлений и координации команды.",
+  "wizardChannelFeature1": "Публичный канал для общей связи команды",
+  "wizardChannelFeature2": "Создавайте пользовательские каналы для отдельных групп",
+  "wizardChannelFeature3": "Сообщения автоматически ретранслируются через mesh",
+  "wizardContactsTitle": "Контакты",
+  "wizardContactsDescription": "Члены вашей команды появляются автоматически по мере подключения к mesh-сети. Отправляйте им личные сообщения или просматривайте их местоположение.",
+  "wizardContactsFeature1": "Контакты обнаруживаются автоматически",
+  "wizardContactsFeature2": "Отправка личных сообщений",
+  "wizardContactsFeature3": "Просмотр уровня заряда и времени последнего появления",
+  "wizardMapTitle": "Карта и местоположение",
+  "wizardMapDescription": "Отслеживайте команду в реальном времени и отмечайте важные места для поисково-спасательных операций.",
+  "wizardMapFeature1": "Маркеры SAR для найденных людей, пожаров и мест сбора",
+  "wizardMapFeature2": "GPS-отслеживание членов команды в реальном времени",
+  "wizardMapFeature3": "Загрузка офлайн-карт для отдалённых районов",
+  "wizardMapFeature4": "Рисование фигур и обмен тактической информацией",
+  "viewWelcomeTutorial": "Просмотреть обучение",
+  "allTeamContacts": "Все контакты команды",
+  "directMessagesInfo": "Личные сообщения с подтверждением. Отправлено {count} членам команды.",
+  "sarMarkerSentToContacts": "Маркер SAR отправлен {count} контактам",
+  "noContactsAvailable": "Нет доступных контактов команды",
+  "reply": "Ответить",
+  "technicalDetails": "Технические детали",
+  "messageTechnicalDetails": "Технические детали сообщения",
+  "linkQuality": "Качество связи",
+  "delivery": "Доставка",
+  "status": "Статус",
+  "expectedAckTag": "Ожидаемый тег ACK",
+  "roundTrip": "Время отклика",
+  "retryAttempt": "Попытка повтора",
+  "floodFallback": "Широковещательный резерв",
+  "identity": "Идентификатор",
+  "messageId": "ID сообщения",
+  "sender": "Отправитель",
+  "senderKey": "Ключ отправителя",
+  "recipient": "Получатель",
+  "recipientKey": "Ключ получателя",
+  "voice": "Голос",
+  "voiceId": "ID голоса",
+  "envelope": "Конверт",
+  "sessionProgress": "Прогресс сессии",
+  "complete": "Завершено",
+  "rawDump": "Необработанные данные",
+  "cannotRetryMissingRecipient": "Повтор невозможен: нет информации о получателе",
+  "voiceUnavailable": "Голос сейчас недоступен",
+  "requestingVoice": "Запрос голоса",
+  "device": "устройство",
+  "change": "Изменить",
+  "wizardOverviewDescription": "Это приложение объединяет сообщения MeshCore, полевые обновления SAR, карты и инструменты устройства в одном месте.",
+  "wizardOverviewFeature1": "Отправляйте личные сообщения, сообщения комнат и сообщения каналов из основной вкладки «Сообщения».",
+  "wizardOverviewFeature2": "Делитесь SAR-маркерами, рисунками на карте, голосовыми клипами и изображениями через mesh-сеть.",
+  "wizardOverviewFeature3": "Подключайтесь по BLE или TCP, а затем управляйте сопутствующей радиостанцией прямо из приложения.",
+  "wizardMessagingTitle": "Сообщения и полевые отчёты",
+  "wizardMessagingDescription": "Здесь сообщения это больше, чем просто текст. Приложение уже поддерживает несколько видов операционных данных и сценариев передачи.",
+  "wizardMessagingFeature1": "Отправляйте личные сообщения, сообщения комнат и трафик каналов из одного редактора.",
+  "wizardMessagingFeature2": "Создавайте обновления SAR и повторно используемые шаблоны SAR для типовых полевых отчётов.",
+  "wizardMessagingFeature3": "Передавайте голосовые сессии и изображения с индикатором прогресса и оценкой эфирного времени в интерфейсе.",
+  "wizardConnectDeviceTitle": "Подключить устройство",
+  "wizardConnectDeviceDescription": "Подключите свою радиостанцию MeshCore, выберите имя и примените радиопрофиль перед продолжением.",
+  "wizardSetupBadge": "Настройка",
+  "wizardOverviewBadge": "Обзор",
+  "wizardConnectedToDevice": "Подключено к {deviceName}",
+  "wizardNoDeviceConnected": "Устройство ещё не подключено",
+  "wizardSkipForNow": "Пропустить пока",
+  "wizardDeviceNameLabel": "Имя устройства",
+  "wizardDeviceNameHelp": "Это имя транслируется другим пользователям MeshCore.",
+  "wizardConfigRegionLabel": "Регион конфигурации",
+  "wizardConfigRegionHelp": "Используется полный официальный список профилей MeshCore. По умолчанию выбран EU/UK (Narrow).",
+  "wizardPresetNote1": "Убедитесь, что выбранный профиль соответствует местным радиоправилам.",
+  "wizardPresetNote2": "Список соответствует официальному потоку профилей инструмента MeshCore config.",
+  "wizardPresetNote3": "Для онбординга по умолчанию остаётся выбран EU/UK (Narrow).",
+  "wizardSaving": "Сохранение...",
+  "wizardSaveAndContinue": "Сохранить и продолжить",
+  "wizardEnterDeviceName": "Введите имя устройства перед продолжением.",
+  "wizardDeviceSetupSaved": "Сохранено: {deviceName}, профиль {presetName}.",
+  "wizardNetworkTitle": "Контакты, комнаты и ретрансляторы",
+  "wizardNetworkDescription": "Вкладка «Контакты» организует сеть, которую вы обнаруживаете, и маршруты, которые вы узнаёте со временем.",
+  "wizardNetworkFeature1": "Просматривайте участников команды, ретрансляторы, комнаты, каналы и ожидающие объявления в одном списке.",
+  "wizardNetworkFeature2": "Используйте smart ping, вход в комнаты, изученные пути и инструменты сброса маршрутов, когда связь становится нестабильной.",
+  "wizardNetworkFeature3": "Создавайте каналы и управляйте сетевыми назначениями, не покидая приложение.",
+  "wizardMapOpsTitle": "Карта, следы и общая геометрия",
+  "wizardMapOpsDescription": "Карта приложения напрямую связана с сообщениями, отслеживанием и SAR-слоями, а не является отдельным просмотрщиком.",
+  "wizardMapOpsFeature1": "Отслеживайте свою позицию, местоположение команды и траектории движения на карте.",
+  "wizardMapOpsFeature2": "Открывайте рисунки из сообщений, просматривайте их прямо в интерфейсе и удаляйте с карты при необходимости.",
+  "wizardMapOpsFeature3": "Используйте карты ретрансляторов и общие слои, чтобы понимать покрытие сети в поле.",
+  "wizardToolsTitle": "Инструменты помимо сообщений",
+  "wizardToolsDescription": "Здесь есть больше, чем четыре основные вкладки. Приложение также включает настройку, диагностику и необязательные сценарии датчиков.",
+  "wizardToolsFeature1": "Откройте настройки устройства, чтобы изменить параметры радио, телеметрию, мощность TX и сведения о сопутствующем устройстве.",
+  "wizardToolsFeature2": "Включите вкладку «Датчики», если нужны панели наблюдаемых датчиков и быстрые действия обновления.",
+  "wizardToolsFeature3": "Используйте журналы пакетов, сканирование спектра и диагностику разработчика для устранения проблем mesh-сети.",
+  "contactInSensors": "В датчиках",
+  "contactAddToSensors": "Добавить в датчики",
+  "contactSetPath": "Задать путь",
+  "contactAddedToSensors": "{contactName} добавлен в Датчики",
+  "contactFailedToClearRoute": "Не удалось очистить маршрут: {error}",
+  "contactRouteCleared": "Маршрут очищен",
+  "contactRouteSet": "Маршрут задан: {route}",
+  "contactFailedToSetRoute": "Не удалось задать маршрут: {error}"
+}

lib/main.dart

@@ -1,4 +1,7 @@
-import 'dart:io' show Platform;
+import 'dart:async';
+
+import 'package:flutter/foundation.dart'
+    show TargetPlatform, defaultTargetPlatform, kIsWeb;
 import 'package:flutter/material.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:provider/provider.dart';
@@ -14,11 +17,12 @@ import 'providers/channels_provider.dart';
 import 'providers/voice_provider.dart';
 import 'providers/image_provider.dart' as ip;
 import 'providers/app_provider.dart';
+import 'providers/sensors_provider.dart';
 import 'services/voice_codec_service.dart';
 import 'services/voice_player_service.dart';
-import 'services/tile_cache_service.dart';
 import 'services/notification_service.dart';
 import 'services/locale_preferences.dart';
+import 'services/mesh_map_nodes_service.dart';
 import 'services/update_checker_service.dart';
 import 'services/wizard_preferences.dart';
 import 'screens/home_screen.dart';
@@ -70,6 +74,9 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
     // Shows notification if update is available
     _checkForUpdates();
 
+    // Refresh remote mesh node cache in background when the app starts.
+    unawaited(MeshMapNodesService.syncInBackgroundIfStale());
+
     setState(() {
       _wizardCompleted = wizardCompleted;
       _isInitialized = true;
@@ -158,7 +165,7 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
   /// Shows notification if update is available
   Future<void> _checkForUpdates() async {
     // Only check for updates on Android
-    if (!Platform.isAndroid) {
+    if (kIsWeb || defaultTargetPlatform != TargetPlatform.android) {
       debugPrint('[UpdateChecker] Skipping update check (not Android)');
       return;
     }
@@ -234,6 +241,7 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
           },
         ),
         ChangeNotifierProvider(create: (_) => ChannelsProvider()),
+        ChangeNotifierProvider(create: (_) => SensorsProvider()),
 
         // Voice provider (packet reassembly + playback)
         ChangeNotifierProvider(
@@ -246,18 +254,14 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
         // Image provider (fragment reassembly + outgoing session cache)
         ChangeNotifierProvider(create: (_) => ip.ImageProvider()),
 
-        // Tile cache service
-        Provider(create: (_) => TileCacheService()),
-
         // App provider that coordinates everything
         // VoiceProvider is read via context.read inside create since it's already registered above
-        ChangeNotifierProxyProvider6<
+        ChangeNotifierProxyProvider5<
           ConnectionProvider,
           ContactsProvider,
           MessagesProvider,
           DrawingProvider,
           ChannelsProvider,
-          TileCacheService,
           AppProvider
         >(
           create: (context) => AppProvider(
@@ -268,7 +272,6 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
             channelsProvider: context.read<ChannelsProvider>(),
             voiceProvider: context.read<VoiceProvider>(),
             imageProvider: context.read<ip.ImageProvider>(),
-            tileCacheService: context.read<TileCacheService>(),
           ),
           update:
               (
@@ -278,7 +281,6 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
                 messages,
                 drawings,
                 channels,
-                tileCache,
                 previous,
               ) =>
                   previous ??
@@ -290,7 +292,6 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
                     channelsProvider: channels,
                     voiceProvider: context.read<VoiceProvider>(),
                     imageProvider: context.read<ip.ImageProvider>(),
-                    tileCacheService: tileCache,
                   ),
         ),
       ],
@@ -330,7 +331,7 @@ class _MeshCoreSarAppState extends State<MeshCoreSarApp> {
 
         // Wrap in SafeArea for Android only to fix navigation bar overlap (API ≥36)
         // iOS doesn't need SafeArea wrapping (causes extra black space at bottom)
-        if (Platform.isAndroid) {
+        if (!kIsWeb && defaultTargetPlatform == TargetPlatform.android) {
           return SafeArea(
             left: false,
             right: false,

lib/models/contact.dart

@@ -1,10 +1,186 @@
 export 'package:meshcore_client/meshcore_client.dart'
     show Contact, ContactType, ContactTelemetry, AdvertLocation;
 
+import 'dart:math' as math;
+import 'dart:typed_data';
 import 'package:flutter/material.dart';
 import '../l10n/app_localizations.dart';
 import 'package:meshcore_client/meshcore_client.dart';
 
+class ParsedContactRoute {
+  final String canonicalText;
+  final int hashSize;
+  final int hopCount;
+  final int encodedPathLen;
+  final int signedEncodedPathLen;
+  final Uint8List pathBytes;
+  final Uint8List paddedPathBytes;
+
+  const ParsedContactRoute({
+    required this.canonicalText,
+    required this.hashSize,
+    required this.hopCount,
+    required this.encodedPathLen,
+    required this.signedEncodedPathLen,
+    required this.pathBytes,
+    required this.paddedPathBytes,
+  });
+
+  int get byteLength => pathBytes.length;
+  String get summary => hopCount == 0
+      ? 'Direct'
+      : '$hopCount hop${hopCount == 1 ? '' : 's'} via $hashSize-byte hashes';
+}
+
+class ContactRouteFormatException implements Exception {
+  final String message;
+
+  const ContactRouteFormatException(this.message);
+
+  @override
+  String toString() => message;
+}
+
+class ContactRouteCodec {
+  static const int maxHashSize = 3;
+  static const int maxPathBytes = 64;
+  static const int _unknownDescriptor = 0xFF;
+
+  static ParsedContactRoute parse(String input, {int? expectedHashSize}) {
+    final normalized = input.trim().toUpperCase();
+    if (normalized.isEmpty) {
+      throw const ContactRouteFormatException('Route cannot be empty.');
+    }
+
+    if (expectedHashSize != null &&
+        (expectedHashSize < 1 || expectedHashSize > maxHashSize)) {
+      throw const ContactRouteFormatException(
+        'Hash size must be 1, 2, or 3 bytes.',
+      );
+    }
+
+    final hopTokens = normalized
+        .split(',')
+        .map((token) => token.trim())
+        .toList();
+    if (hopTokens.any((token) => token.isEmpty)) {
+      throw const ContactRouteFormatException('Route contains an empty hop.');
+    }
+
+    final hopBytes = <List<int>>[];
+    int? hashSize;
+    for (final token in hopTokens) {
+      final compact = token.replaceAll(':', '');
+      if (compact.isEmpty || !RegExp(r'^[0-9A-F]+$').hasMatch(compact)) {
+        throw ContactRouteFormatException('Invalid hop "$token".');
+      }
+      if (compact.length.isOdd) {
+        throw ContactRouteFormatException(
+          'Hop "$token" must contain full bytes.',
+        );
+      }
+
+      final currentHashSize = compact.length ~/ 2;
+      if (currentHashSize < 1 || currentHashSize > maxHashSize) {
+        throw ContactRouteFormatException(
+          'Hop "$token" must be 1, 2, or 3 bytes.',
+        );
+      }
+
+      if (expectedHashSize != null && currentHashSize != expectedHashSize) {
+        throw ContactRouteFormatException(
+          'Hop "$token" must be $expectedHashSize '
+          'byte${expectedHashSize == 1 ? '' : 's'}.',
+        );
+      }
+
+      hashSize ??= currentHashSize;
+      if (hashSize != currentHashSize) {
+        throw const ContactRouteFormatException(
+          'All hops in a route must use the same hash size.',
+        );
+      }
+
+      final bytes = <int>[];
+      for (var i = 0; i < compact.length; i += 2) {
+        bytes.add(int.parse(compact.substring(i, i + 2), radix: 16));
+      }
+      hopBytes.add(bytes);
+    }
+
+    final resolvedHashSize = hashSize ?? 1;
+    final flatBytes = Uint8List.fromList(
+      hopBytes.expand((hop) => hop).toList(),
+    );
+    if (flatBytes.length > maxPathBytes) {
+      throw const ContactRouteFormatException(
+        'Route exceeds the 64-byte firmware limit.',
+      );
+    }
+
+    final encodedPathLen =
+        ((resolvedHashSize - 1) << 6) | (hopBytes.length & 0x3F);
+    final padded = Uint8List(maxPathBytes);
+    padded.setRange(0, flatBytes.length, flatBytes);
+
+    return ParsedContactRoute(
+      canonicalText: hopBytes
+          .map(
+            (hop) => hop
+                .map((byte) => byte.toRadixString(16).padLeft(2, '0'))
+                .join()
+                .toUpperCase(),
+          )
+          .join(','),
+      hashSize: resolvedHashSize,
+      hopCount: hopBytes.length,
+      encodedPathLen: encodedPathLen,
+      signedEncodedPathLen: toSignedDescriptor(encodedPathLen),
+      pathBytes: flatBytes,
+      paddedPathBytes: padded,
+    );
+  }
+
+  static ParsedContactRoute? fromContact(Contact contact) {
+    if (!contact.routeHasPath || contact.routeHopCount == 0) {
+      return null;
+    }
+
+    return ParsedContactRoute(
+      canonicalText: contact.routeCanonicalText,
+      hashSize: contact.routeHashSize,
+      hopCount: contact.routeHopCount,
+      encodedPathLen: contact.routeEncodedPathLen,
+      signedEncodedPathLen: contact.routeSignedPathLen,
+      pathBytes: contact.routePathBytes,
+      paddedPathBytes: _padPath(contact.routePathBytes),
+    );
+  }
+
+  static Uint8List _padPath(Uint8List bytes) {
+    final padded = Uint8List(maxPathBytes);
+    padded.setRange(0, math.min(bytes.length, maxPathBytes), bytes);
+    return padded;
+  }
+
+  static int toSignedDescriptor(int encodedPathLen) =>
+      encodedPathLen > 127 ? encodedPathLen - 256 : encodedPathLen;
+
+  static int toUnsignedDescriptor(int signedPathLen) => signedPathLen & 0xFF;
+
+  static bool isUnknownDescriptor(int signedPathLen) =>
+      toUnsignedDescriptor(signedPathLen) == _unknownDescriptor;
+
+  static bool isValidDescriptor(int signedPathLen) {
+    final raw = toUnsignedDescriptor(signedPathLen);
+    if (raw == _unknownDescriptor) return false;
+    final hashSize = ((raw >> 6) + 1);
+    if (hashSize > maxHashSize) return false;
+    final hopCount = raw & 0x3F;
+    return hopCount * hashSize <= maxPathBytes;
+  }
+}
+
 extension ContactLocalization on Contact {
   /// Returns the localized display name for special contacts (e.g. Public Channel).
   /// For all other contacts, returns [displayName].
@@ -14,4 +190,55 @@ extension ContactLocalization on Contact {
     }
     return displayName;
   }
+
+  int get routeEncodedPathLen =>
+      ContactRouteCodec.toUnsignedDescriptor(outPathLen);
+
+  int get routeSignedPathLen =>
+      ContactRouteCodec.toSignedDescriptor(routeEncodedPathLen);
+
+  bool get routeIsUnknown => ContactRouteCodec.isUnknownDescriptor(outPathLen);
+
+  bool get routeHasPath =>
+      !routeIsUnknown && ContactRouteCodec.isValidDescriptor(outPathLen);
+
+  int get routeHashSize => routeHasPath ? ((routeEncodedPathLen >> 6) + 1) : 1;
+
+  int get routeHopCount => routeHasPath ? (routeEncodedPathLen & 0x3F) : -1;
+
+  int get routeByteLength => routeHasPath
+      ? math.min(routeHopCount * routeHashSize, outPath.length)
+      : 0;
+
+  Uint8List get routePathBytes => routeByteLength <= 0
+      ? Uint8List(0)
+      : Uint8List.fromList(outPath.sublist(0, routeByteLength));
+
+  String get routeCanonicalText {
+    if (!routeHasPath || routeHopCount <= 0) return '';
+    final bytes = routePathBytes;
+    final hops = <String>[];
+    for (var i = 0; i < bytes.length; i += routeHashSize) {
+      hops.add(
+        bytes
+            .sublist(i, i + routeHashSize)
+            .map((byte) => byte.toRadixString(16).padLeft(2, '0'))
+            .join()
+            .toUpperCase(),
+      );
+    }
+    return hops.join(',');
+  }
+
+  String get routeSummary {
+    if (routeIsUnknown) {
+      return 'Flood/Unknown';
+    }
+    if (!routeHasPath || routeHopCount == 0) {
+      return 'Direct';
+    }
+    return '$routeHopCount hop${routeHopCount == 1 ? '' : 's'} via $routeHashSize-byte hashes';
+  }
+
+  bool get routeSupportsLegacyRawTransport => routeHasPath;
 }

lib/models/device_info.dart

@@ -73,12 +73,14 @@ class DeviceInfo {
   final String? selfName;
 
   // Additional device capabilities (from RESP_CODE_DEVICE_INFO)
-  final int? maxContacts;        // Max contacts device supports
-  final int? maxChannels;        // Max channels device supports
-  final int? telemetryModes;     // Telemetry permission modes (bits 0-1: Base, bits 2-3: Location)
-  final int? blePin;             // BLE PIN code
-  final int? multiAcks;          // Extra ACK mode (0=no, 1=yes)
-  final int? advertLocPolicy;    // Location sharing policy (0=don't share, 1=share)
+  final int? maxContacts; // Max contacts device supports
+  final int? maxChannels; // Max channels device supports
+  final int?
+  telemetryModes; // Telemetry permission modes (bits 0-1: Base, bits 2-3: Location)
+  final int? blePin; // BLE PIN code
+  final int? multiAcks; // Extra ACK mode (0=no, 1=yes)
+  final int?
+  advertLocPolicy; // Location sharing policy (0=don't share, 1=share)
 
   // Firmware info
   final int? firmwareVersion;
@@ -88,6 +90,9 @@ class DeviceInfo {
 
   // Repeat mode (firmware v9+)
   final bool? clientRepeat;
+  final bool? supportsSpectrumScan;
+  final int? spectrumScanMinKhz;
+  final int? spectrumScanMaxKhz;
   final List<({int lower, int upper})>? allowedRepeatFreqRanges;
 
   DeviceInfo({
@@ -124,6 +129,9 @@ class DeviceInfo {
     this.manufacturerModel,
     this.semanticVersion,
     this.clientRepeat,
+    this.supportsSpectrumScan,
+    this.spectrumScanMinKhz,
+    this.spectrumScanMaxKhz,
     this.allowedRepeatFreqRanges,
   });
 
@@ -160,7 +168,9 @@ class DeviceInfo {
 
   /// Get storage usage percentage (0-100)
   double? get storageUsedPercent {
-    if (storageUsedKb == null || storageTotalKb == null || storageTotalKb == 0) {
+    if (storageUsedKb == null ||
+        storageTotalKb == null ||
+        storageTotalKb == 0) {
       return null;
     }
     return (storageUsedKb! / storageTotalKb!) * 100.0;
@@ -245,6 +255,9 @@ class DeviceInfo {
     String? manufacturerModel,
     String? semanticVersion,
     bool? clientRepeat,
+    bool? supportsSpectrumScan,
+    int? spectrumScanMinKhz,
+    int? spectrumScanMaxKhz,
     List<({int lower, int upper})>? allowedRepeatFreqRanges,
   }) {
     return DeviceInfo(
@@ -281,7 +294,11 @@ class DeviceInfo {
       manufacturerModel: manufacturerModel ?? this.manufacturerModel,
       semanticVersion: semanticVersion ?? this.semanticVersion,
       clientRepeat: clientRepeat ?? this.clientRepeat,
-      allowedRepeatFreqRanges: allowedRepeatFreqRanges ?? this.allowedRepeatFreqRanges,
+      supportsSpectrumScan: supportsSpectrumScan ?? this.supportsSpectrumScan,
+      spectrumScanMinKhz: spectrumScanMinKhz ?? this.spectrumScanMinKhz,
+      spectrumScanMaxKhz: spectrumScanMaxKhz ?? this.spectrumScanMaxKhz,
+      allowedRepeatFreqRanges:
+          allowedRepeatFreqRanges ?? this.allowedRepeatFreqRanges,
     );
   }
 

lib/models/map_layer.dart

@@ -1,4 +1,3 @@
-import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
 import '../l10n/app_localizations.dart';
@@ -10,6 +9,7 @@ enum MapLayerType {
   googleHybrid,
   googleRoadmap,
   googleTerrain,
+  // Kept for stored preference compatibility after MBTiles removal.
   vectorMbtiles,
   wmsBase,
 }
@@ -21,13 +21,6 @@ class MapLayer {
   final String attribution;
   final double maxZoom;
 
-  // Vector tile specific properties
-  final bool isVector;
-  final File? mbtilesFile;
-  final String? styleUrl;
-  final String? sourceName;
-  final bool? isGzipped;
-
   // WMS specific properties
   final bool isWms;
   final String? wmsBaseUrl;
@@ -43,11 +36,6 @@ class MapLayer {
     required this.urlTemplate,
     required this.attribution,
     required this.maxZoom,
-    this.isVector = false,
-    this.mbtilesFile,
-    this.styleUrl,
-    this.sourceName,
-    this.isGzipped,
     this.isWms = false,
     this.wmsBaseUrl,
     this.wmsLayers,
@@ -74,7 +62,7 @@ class MapLayer {
       case MapLayerType.googleTerrain:
         return localizations.googleTerrain;
       case MapLayerType.vectorMbtiles:
-        // For vector tiles, use the name from metadata
+        // Legacy value kept only for preference migration compatibility.
         return name;
       case MapLayerType.wmsBase:
         // For WMS layers, use the name (will be localized separately)
@@ -182,28 +170,4 @@ class MapLayer {
   static MapLayer fromType(MapLayerType type) {
     return allLayers.firstWhere((layer) => layer.type == type);
   }
-
-  /// Create a MapLayer from an MBTiles file
-  static MapLayer fromMbtilesFile({
-    required String name,
-    required File mbtilesFile,
-    required String styleUrl,
-    required String sourceName,
-    required double maxZoom,
-    required bool isGzipped,
-    String? attribution,
-  }) {
-    return MapLayer(
-      type: MapLayerType.vectorMbtiles,
-      name: name,
-      urlTemplate: '', // Not used for vector tiles
-      attribution: attribution ?? 'MBTiles',
-      maxZoom: maxZoom,
-      isVector: true,
-      mbtilesFile: mbtilesFile,
-      styleUrl: styleUrl,
-      sourceName: sourceName,
-      isGzipped: isGzipped,
-    );
-  }
 }

lib/models/message_contact_location.dart

@@ -0,0 +1,63 @@
+import 'package:latlong2/latlong.dart';
+
+class MessageContactLocation {
+  final LatLng location;
+  final String source;
+  final DateTime capturedAt;
+  final DateTime? sourceTimestamp;
+
+  const MessageContactLocation({
+    required this.location,
+    required this.source,
+    required this.capturedAt,
+    this.sourceTimestamp,
+  });
+
+  String get technicalSourceLabel {
+    switch (source) {
+      case 'telemetry':
+        return 'telemetry';
+      case 'advert':
+        return 'advert';
+      default:
+        return source;
+    }
+  }
+
+  String get formattedCoordinates =>
+      '${location.latitude.toStringAsFixed(6)}, ${location.longitude.toStringAsFixed(6)}';
+
+  Map<String, dynamic> toJson() {
+    return {
+      'latitude': location.latitude,
+      'longitude': location.longitude,
+      'source': source,
+      'capturedAtMillis': capturedAt.millisecondsSinceEpoch,
+      'sourceTimestampMillis': sourceTimestamp?.millisecondsSinceEpoch,
+    };
+  }
+
+  static MessageContactLocation? fromJson(Map<String, dynamic> json) {
+    final latitude = json['latitude'];
+    final longitude = json['longitude'];
+    final source = json['source'];
+    final capturedAtMillis = json['capturedAtMillis'];
+    if (latitude is! num ||
+        longitude is! num ||
+        source is! String ||
+        capturedAtMillis is! int) {
+      return null;
+    }
+
+    return MessageContactLocation(
+      location: LatLng(latitude.toDouble(), longitude.toDouble()),
+      source: source,
+      capturedAt: DateTime.fromMillisecondsSinceEpoch(capturedAtMillis),
+      sourceTimestamp: json['sourceTimestampMillis'] is int
+          ? DateTime.fromMillisecondsSinceEpoch(
+              json['sourceTimestampMillis'] as int,
+            )
+          : null,
+    );
+  }
+}

lib/models/message_reception_details.dart

@@ -0,0 +1,86 @@
+const int _transmitEstimateToleranceMs = 1500;
+
+int? sanitizeEstimatedTransmitMs({
+  required int? estimatedTransmitMs,
+  required int? senderToReceiptMs,
+}) {
+  if (estimatedTransmitMs == null || estimatedTransmitMs <= 0) {
+    return null;
+  }
+
+  if (senderToReceiptMs == null || senderToReceiptMs <= 0) {
+    return estimatedTransmitMs;
+  }
+
+  // Sender timestamps are second-granularity, so allow a small cushion before
+  // treating the estimate as impossible for the observed delivery time.
+  if (estimatedTransmitMs > senderToReceiptMs + _transmitEstimateToleranceMs) {
+    return null;
+  }
+
+  return estimatedTransmitMs;
+}
+
+class MessageReceptionDetails {
+  final DateTime capturedAt;
+  final DateTime? packetLoggedAt;
+  final int? rssiDbm;
+  final double? snrDb;
+  final List<int>? pathBytes;
+  final int? senderToReceiptMs;
+  final int? estimatedTransmitMs;
+  final int? postTransmitDelayMs;
+
+  const MessageReceptionDetails({
+    required this.capturedAt,
+    this.packetLoggedAt,
+    this.rssiDbm,
+    this.snrDb,
+    this.pathBytes,
+    this.senderToReceiptMs,
+    this.estimatedTransmitMs,
+    this.postTransmitDelayMs,
+  });
+
+  String? get pathBytesHex => pathBytes == null || pathBytes!.isEmpty
+      ? null
+      : pathBytes!.map((b) => b.toRadixString(16).padLeft(2, '0')).join(':');
+
+  Map<String, dynamic> toJson() {
+    return {
+      'capturedAtMillis': capturedAt.millisecondsSinceEpoch,
+      'packetLoggedAtMillis': packetLoggedAt?.millisecondsSinceEpoch,
+      'rssiDbm': rssiDbm,
+      'snrDb': snrDb,
+      'pathBytes': pathBytes,
+      'senderToReceiptMs': senderToReceiptMs,
+      'estimatedTransmitMs': estimatedTransmitMs,
+      'postTransmitDelayMs': postTransmitDelayMs,
+    };
+  }
+
+  static MessageReceptionDetails? fromJson(Map<String, dynamic> json) {
+    final capturedAtMillis = json['capturedAtMillis'];
+    if (capturedAtMillis is! int) {
+      return null;
+    }
+
+    final pathBytes = json['pathBytes'];
+    return MessageReceptionDetails(
+      capturedAt: DateTime.fromMillisecondsSinceEpoch(capturedAtMillis),
+      packetLoggedAt: json['packetLoggedAtMillis'] is int
+          ? DateTime.fromMillisecondsSinceEpoch(
+              json['packetLoggedAtMillis'] as int,
+            )
+          : null,
+      rssiDbm: json['rssiDbm'] as int?,
+      snrDb: (json['snrDb'] as num?)?.toDouble(),
+      pathBytes: pathBytes is List
+          ? pathBytes.whereType<num>().map((b) => b.toInt()).toList()
+          : null,
+      senderToReceiptMs: json['senderToReceiptMs'] as int?,
+      estimatedTransmitMs: json['estimatedTransmitMs'] as int?,
+      postTransmitDelayMs: json['postTransmitDelayMs'] as int?,
+    );
+  }
+}

lib/models/message_route_metadata.dart

@@ -0,0 +1,79 @@
+import 'path_selection.dart';
+
+class MessageRouteMetadata {
+  final PathSelectionMode mode;
+  final bool routerFallbackAttempted;
+  final String? relayName;
+  final String? relayKey6;
+  final String? canonicalPath;
+  final int? hopCount;
+
+  const MessageRouteMetadata({
+    required this.mode,
+    required this.routerFallbackAttempted,
+    this.relayName,
+    this.relayKey6,
+    this.canonicalPath,
+    this.hopCount,
+  });
+
+  factory MessageRouteMetadata.fromSelection(
+    PathSelection selection, {
+    required bool routerFallbackAttempted,
+  }) {
+    return MessageRouteMetadata(
+      mode: selection.mode,
+      routerFallbackAttempted: routerFallbackAttempted,
+      relayName: selection.relayName,
+      relayKey6: selection.relayKey6,
+      canonicalPath: selection.canonicalPath.isEmpty
+          ? null
+          : selection.canonicalPath,
+      hopCount: selection.hopCount > 0 ? selection.hopCount : null,
+    );
+  }
+
+  String get modeLabel {
+    switch (mode) {
+      case PathSelectionMode.directCurrent:
+        return 'Current direct path';
+      case PathSelectionMode.directHistorical:
+        return 'Rotated direct path';
+      case PathSelectionMode.flood:
+        return 'Flood route';
+      case PathSelectionMode.nearestRouter:
+        final suffix = relayName?.trim().isNotEmpty == true
+            ? ' via $relayName'
+            : relayKey6?.trim().isNotEmpty == true
+            ? ' via $relayKey6'
+            : '';
+        return 'Nearest router$suffix';
+    }
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'mode': mode.name,
+      'router_fallback_attempted': routerFallbackAttempted,
+      'relay_name': relayName,
+      'relay_key6': relayKey6,
+      'canonical_path': canonicalPath,
+      'hop_count': hopCount,
+    };
+  }
+
+  factory MessageRouteMetadata.fromJson(Map<String, dynamic> json) {
+    return MessageRouteMetadata(
+      mode: PathSelectionMode.values.firstWhere(
+        (value) => value.name == json['mode'],
+        orElse: () => PathSelectionMode.directCurrent,
+      ),
+      routerFallbackAttempted:
+          json['router_fallback_attempted'] as bool? ?? false,
+      relayName: json['relay_name'] as String?,
+      relayKey6: json['relay_key6'] as String?,
+      canonicalPath: json['canonical_path'] as String?,
+      hopCount: json['hop_count'] as int?,
+    );
+  }
+}

lib/models/message_transfer_details.dart

@@ -0,0 +1,142 @@
+class MessageTransferDownloader {
+  final String requesterKey6;
+  final String? requesterName;
+  final int transferCount;
+  final DateTime lastTransferredAt;
+
+  const MessageTransferDownloader({
+    required this.requesterKey6,
+    this.requesterName,
+    required this.transferCount,
+    required this.lastTransferredAt,
+  });
+
+  MessageTransferDownloader copyWith({
+    String? requesterKey6,
+    String? requesterName,
+    int? transferCount,
+    DateTime? lastTransferredAt,
+  }) {
+    return MessageTransferDownloader(
+      requesterKey6: requesterKey6 ?? this.requesterKey6,
+      requesterName: requesterName ?? this.requesterName,
+      transferCount: transferCount ?? this.transferCount,
+      lastTransferredAt: lastTransferredAt ?? this.lastTransferredAt,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'requesterKey6': requesterKey6,
+      'requesterName': requesterName,
+      'transferCount': transferCount,
+      'lastTransferredAtMillis': lastTransferredAt.millisecondsSinceEpoch,
+    };
+  }
+
+  static MessageTransferDownloader? fromJson(Map<String, dynamic> json) {
+    final requesterKey6 = json['requesterKey6'];
+    final transferCount = json['transferCount'];
+    final lastTransferredAtMillis = json['lastTransferredAtMillis'];
+    if (requesterKey6 is! String ||
+        transferCount is! int ||
+        lastTransferredAtMillis is! int) {
+      return null;
+    }
+
+    return MessageTransferDownloader(
+      requesterKey6: requesterKey6,
+      requesterName: json['requesterName'] as String?,
+      transferCount: transferCount,
+      lastTransferredAt: DateTime.fromMillisecondsSinceEpoch(
+        lastTransferredAtMillis,
+      ),
+    );
+  }
+}
+
+class MessageTransferDetails {
+  final int totalTransfers;
+  final List<MessageTransferDownloader> downloaders;
+
+  const MessageTransferDetails({
+    required this.totalTransfers,
+    required this.downloaders,
+  });
+
+  const MessageTransferDetails.empty()
+    : totalTransfers = 0,
+      downloaders = const [];
+
+  MessageTransferDetails registerTransfer({
+    required String requesterKey6,
+    String? requesterName,
+    DateTime? transferredAt,
+  }) {
+    final eventAt = transferredAt ?? DateTime.now();
+    final normalizedName = requesterName?.trim();
+    final updatedDownloaders = List<MessageTransferDownloader>.from(
+      downloaders,
+    );
+    final index = updatedDownloaders.indexWhere(
+      (entry) => entry.requesterKey6 == requesterKey6,
+    );
+
+    if (index == -1) {
+      updatedDownloaders.add(
+        MessageTransferDownloader(
+          requesterKey6: requesterKey6,
+          requesterName: normalizedName?.isEmpty ?? true
+              ? null
+              : normalizedName,
+          transferCount: 1,
+          lastTransferredAt: eventAt,
+        ),
+      );
+    } else {
+      final existing = updatedDownloaders[index];
+      updatedDownloaders[index] = existing.copyWith(
+        requesterName: normalizedName?.isEmpty ?? true
+            ? existing.requesterName
+            : normalizedName,
+        transferCount: existing.transferCount + 1,
+        lastTransferredAt: eventAt,
+      );
+    }
+
+    updatedDownloaders.sort(
+      (a, b) => b.lastTransferredAt.compareTo(a.lastTransferredAt),
+    );
+
+    return MessageTransferDetails(
+      totalTransfers: totalTransfers + 1,
+      downloaders: updatedDownloaders,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'totalTransfers': totalTransfers,
+      'downloaders': downloaders.map((entry) => entry.toJson()).toList(),
+    };
+  }
+
+  static MessageTransferDetails? fromJson(Map<String, dynamic> json) {
+    final totalTransfers = json['totalTransfers'];
+    if (totalTransfers is! int) {
+      return null;
+    }
+
+    final rawDownloaders = json['downloaders'] as List<dynamic>? ?? const [];
+    final downloaders = rawDownloaders
+        .whereType<Map<String, dynamic>>()
+        .map(MessageTransferDownloader.fromJson)
+        .whereType<MessageTransferDownloader>()
+        .toList();
+
+    return MessageTransferDetails(
+      totalTransfers: totalTransfers,
+      downloaders: downloaders,
+    );
+  }
+}

lib/models/path_history.dart

@@ -0,0 +1,182 @@
+class PathRecord {
+  final List<int> pathBytes;
+  final int hopCount;
+  final int hashSize;
+  final int successCount;
+  final int failureCount;
+  final int lastRoundTripTimeMs;
+  final DateTime lastUsedAt;
+
+  const PathRecord({
+    required this.pathBytes,
+    required this.hopCount,
+    required this.hashSize,
+    required this.successCount,
+    required this.failureCount,
+    required this.lastRoundTripTimeMs,
+    required this.lastUsedAt,
+  });
+
+  String get signature =>
+      pathBytes.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join();
+
+  double get successRate =>
+      (successCount + 1) / (successCount + failureCount + 2);
+
+  PathRecord copyWith({
+    List<int>? pathBytes,
+    int? hopCount,
+    int? hashSize,
+    int? successCount,
+    int? failureCount,
+    int? lastRoundTripTimeMs,
+    DateTime? lastUsedAt,
+  }) {
+    return PathRecord(
+      pathBytes: pathBytes ?? this.pathBytes,
+      hopCount: hopCount ?? this.hopCount,
+      hashSize: hashSize ?? this.hashSize,
+      successCount: successCount ?? this.successCount,
+      failureCount: failureCount ?? this.failureCount,
+      lastRoundTripTimeMs: lastRoundTripTimeMs ?? this.lastRoundTripTimeMs,
+      lastUsedAt: lastUsedAt ?? this.lastUsedAt,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'path_bytes': pathBytes,
+      'hop_count': hopCount,
+      'hash_size': hashSize,
+      'success_count': successCount,
+      'failure_count': failureCount,
+      'last_round_trip_time_ms': lastRoundTripTimeMs,
+      'last_used_at': lastUsedAt.toIso8601String(),
+    };
+  }
+
+  factory PathRecord.fromJson(Map<String, dynamic> json) {
+    return PathRecord(
+      pathBytes: (json['path_bytes'] as List<dynamic>? ?? const <dynamic>[])
+          .map((value) => value as int)
+          .toList(),
+      hopCount: json['hop_count'] as int? ?? 0,
+      hashSize: json['hash_size'] as int? ?? 1,
+      successCount: json['success_count'] as int? ?? 0,
+      failureCount: json['failure_count'] as int? ?? 0,
+      lastRoundTripTimeMs: json['last_round_trip_time_ms'] as int? ?? 0,
+      lastUsedAt:
+          DateTime.tryParse(json['last_used_at'] as String? ?? '') ??
+          DateTime.fromMillisecondsSinceEpoch(0),
+    );
+  }
+}
+
+class FloodPathStats {
+  final int successCount;
+  final int failureCount;
+  final int lastRoundTripTimeMs;
+  final DateTime? lastUsedAt;
+
+  const FloodPathStats({
+    required this.successCount,
+    required this.failureCount,
+    required this.lastRoundTripTimeMs,
+    required this.lastUsedAt,
+  });
+
+  const FloodPathStats.empty()
+    : successCount = 0,
+      failureCount = 0,
+      lastRoundTripTimeMs = 0,
+      lastUsedAt = null;
+
+  FloodPathStats copyWith({
+    int? successCount,
+    int? failureCount,
+    int? lastRoundTripTimeMs,
+    DateTime? lastUsedAt,
+  }) {
+    return FloodPathStats(
+      successCount: successCount ?? this.successCount,
+      failureCount: failureCount ?? this.failureCount,
+      lastRoundTripTimeMs: lastRoundTripTimeMs ?? this.lastRoundTripTimeMs,
+      lastUsedAt: lastUsedAt ?? this.lastUsedAt,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'success_count': successCount,
+      'failure_count': failureCount,
+      'last_round_trip_time_ms': lastRoundTripTimeMs,
+      'last_used_at': lastUsedAt?.toIso8601String(),
+    };
+  }
+
+  factory FloodPathStats.fromJson(Map<String, dynamic> json) {
+    return FloodPathStats(
+      successCount: json['success_count'] as int? ?? 0,
+      failureCount: json['failure_count'] as int? ?? 0,
+      lastRoundTripTimeMs: json['last_round_trip_time_ms'] as int? ?? 0,
+      lastUsedAt: DateTime.tryParse(json['last_used_at'] as String? ?? ''),
+    );
+  }
+}
+
+class ContactPathHistory {
+  final String contactPublicKeyHex;
+  final List<PathRecord> directPaths;
+  final FloodPathStats floodStats;
+  final int rotationIndex;
+
+  const ContactPathHistory({
+    required this.contactPublicKeyHex,
+    required this.directPaths,
+    required this.floodStats,
+    required this.rotationIndex,
+  });
+
+  const ContactPathHistory.empty(this.contactPublicKeyHex)
+    : directPaths = const <PathRecord>[],
+      floodStats = const FloodPathStats.empty(),
+      rotationIndex = 0;
+
+  ContactPathHistory copyWith({
+    List<PathRecord>? directPaths,
+    FloodPathStats? floodStats,
+    int? rotationIndex,
+  }) {
+    return ContactPathHistory(
+      contactPublicKeyHex: contactPublicKeyHex,
+      directPaths: directPaths ?? this.directPaths,
+      floodStats: floodStats ?? this.floodStats,
+      rotationIndex: rotationIndex ?? this.rotationIndex,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'direct_paths': directPaths.map((record) => record.toJson()).toList(),
+      'flood_stats': floodStats.toJson(),
+      'rotation_index': rotationIndex,
+    };
+  }
+
+  factory ContactPathHistory.fromJson(
+    String contactPublicKeyHex,
+    Map<String, dynamic> json,
+  ) {
+    return ContactPathHistory(
+      contactPublicKeyHex: contactPublicKeyHex,
+      directPaths: (json['direct_paths'] as List<dynamic>? ?? const <dynamic>[])
+          .whereType<Map<String, dynamic>>()
+          .map(PathRecord.fromJson)
+          .toList(),
+      floodStats: json['flood_stats'] is Map<String, dynamic>
+          ? FloodPathStats.fromJson(json['flood_stats'] as Map<String, dynamic>)
+          : const FloodPathStats.empty(),
+      rotationIndex: json['rotation_index'] as int? ?? 0,
+    );
+  }
+}

lib/models/path_selection.dart

@@ -0,0 +1,65 @@
+import 'dart:typed_data';
+
+enum PathSelectionMode { directCurrent, directHistorical, flood, nearestRouter }
+
+class PathSelection {
+  final PathSelectionMode mode;
+  final Uint8List pathBytes;
+  final int hopCount;
+  final int hashSize;
+  final String? relayName;
+  final String? relayKey6;
+
+  const PathSelection({
+    required this.mode,
+    required this.pathBytes,
+    required this.hopCount,
+    required this.hashSize,
+    this.relayName,
+    this.relayKey6,
+  });
+
+  PathSelection.flood()
+    : mode = PathSelectionMode.flood,
+      pathBytes = Uint8List(0),
+      hopCount = -1,
+      hashSize = 1,
+      relayName = null,
+      relayKey6 = null;
+
+  bool get usesFlood => mode == PathSelectionMode.flood;
+  bool get hasDirectPath => !usesFlood && pathBytes.isNotEmpty && hopCount > 0;
+
+  String get canonicalPath {
+    if (!hasDirectPath) return '';
+    final hops = <String>[];
+    for (var index = 0; index < pathBytes.length; index += hashSize) {
+      hops.add(
+        pathBytes
+            .sublist(index, index + hashSize)
+            .map((byte) => byte.toRadixString(16).padLeft(2, '0'))
+            .join()
+            .toUpperCase(),
+      );
+    }
+    return hops.join(',');
+  }
+
+  PathSelection copyWith({
+    PathSelectionMode? mode,
+    Uint8List? pathBytes,
+    int? hopCount,
+    int? hashSize,
+    String? relayName,
+    String? relayKey6,
+  }) {
+    return PathSelection(
+      mode: mode ?? this.mode,
+      pathBytes: pathBytes ?? this.pathBytes,
+      hopCount: hopCount ?? this.hopCount,
+      hashSize: hashSize ?? this.hashSize,
+      relayName: relayName ?? this.relayName,
+      relayKey6: relayKey6 ?? this.relayKey6,
+    );
+  }
+}

lib/providers/connection_provider.dart

@@ -1,12 +1,14 @@
 import 'dart:async';
 import 'dart:convert';
 import 'package:flutter/foundation.dart';
+import 'package:flutter/scheduler.dart';
 import 'package:flutter_blue_plus/flutter_blue_plus.dart';
 import 'package:crypto/crypto.dart';
+import '../models/contact.dart';
 import '../models/device_info.dart';
 import '../models/room_login_state.dart';
 import '../models/sse_server_config.dart';
-import 'package:meshcore_client/meshcore_client.dart';
+import 'package:meshcore_client/meshcore_client.dart' hide Contact;
 import '../services/sse_server_service.dart';
 import '../utils/sar_message_parser.dart';
 import 'helpers/room_login_manager.dart';
@@ -65,8 +67,8 @@ class ConnectionProvider with ChangeNotifier {
   /// Active service — BLE or TCP depending on current mode
   MeshCoreServiceBase get _activeService =>
       (_connectionMode == ConnectionMode.tcp && _tcpService != null)
-          ? _tcpService!
-          : _bleService;
+      ? _tcpService!
+      : _bleService;
 
   /// Current connection mode
   ConnectionMode _connectionMode = ConnectionMode.ble;
@@ -88,6 +90,8 @@ class ConnectionProvider with ChangeNotifier {
 
   bool _isScanning = false;
   bool get isScanning => _isScanning;
+  bool _isSpectrumScanActive = false;
+  bool get isSpectrumScanActive => _isSpectrumScanActive;
 
   String? _error;
   String? get error => _error;
@@ -117,6 +121,8 @@ class ConnectionProvider with ChangeNotifier {
   bool _noMoreMessages = false;
   // Prevent overlapping/too-frequent sync requests
   bool _isSyncingMessages = false;
+  // If MSG_WAITING arrives while a sync loop is active, queue one more pass.
+  bool _syncRequestedWhileBusy = false;
   DateTime? _lastSyncNextRequestedAt;
   static const Duration _minSyncNextInterval = Duration(milliseconds: 150);
 
@@ -141,11 +147,15 @@ class ConnectionProvider with ChangeNotifier {
   final MessageDeliveryTracker _messageDeliveryTracker =
       MessageDeliveryTracker();
   final PingTracker _pingTracker = PingTracker();
+  final Map<String, Future<PingResult>> _pendingSmartPings = {};
 
   // Expose room login states
   Map<String, RoomLoginState> get roomLoginStates =>
       _roomLoginManager.roomLoginStates;
 
+  bool isPingInProgress(Uint8List publicKey) =>
+      _pendingSmartPings.containsKey(_publicKeyToHex(publicKey));
+
   // Callbacks for other providers
   Function(Contact)? onContactReceived;
   Function(List<Contact>)? onContactsComplete;
@@ -165,6 +175,12 @@ class ConnectionProvider with ChangeNotifier {
   Function(String messageId, int expectedAckTag, int suggestedTimeoutMs)?
   onMessageSent;
   Function(int ackCode, int roundTripTimeMs)? onMessageDelivered;
+  Future<Contact?> Function({
+    required String messageId,
+    required Contact contact,
+    required int retryAttempt,
+  })?
+  prepareDirectMessageSendCallback;
   Function(String messageId, int echoCount, int snrRaw, int rssiDbm)?
   onMessageEchoDetected;
   Function(Uint8List publicKeyPrefix, Uint8List statusData)? onStatusResponse;
@@ -244,7 +260,10 @@ class ConnectionProvider with ChangeNotifier {
         await Future.delayed(const Duration(milliseconds: 300));
 
         if (pendingOp.messageId != null) {
-          _messageDeliveryTracker.trackPendingMessage(pendingOp.messageId!);
+          _messageDeliveryTracker.trackPendingDirectMessage(
+            pendingOp.messageId!,
+            pendingOp.contactPublicKey,
+          );
         }
 
         await _activeService.sendTextMessage(
@@ -309,8 +328,19 @@ class ConnectionProvider with ChangeNotifier {
     };
 
     service.onMessageWaiting = () {
+      if (_isSpectrumScanActive) {
+        debugPrint('📥 [Provider] MSG_WAITING ignored during spectrum scan');
+        return;
+      }
       debugPrint('📥 [Provider] MSG_WAITING - auto-syncing');
-      syncAllMessages();
+      if (_isSyncingMessages) {
+        _syncRequestedWhileBusy = true;
+        debugPrint(
+          '  ↪️ [Provider] Sync already running; queued follow-up sync',
+        );
+        return;
+      }
+      unawaited(syncAllMessages());
     };
 
     service.onLoginSuccess =
@@ -336,7 +366,11 @@ class ConnectionProvider with ChangeNotifier {
 
     service.onMessageSent =
         (expectedAckTag, suggestedTimeoutMs, isFloodMode, contactPublicKey) {
-          final messageId = _messageDeliveryTracker.popPendingMessageId();
+          final messageId = contactPublicKey != null
+              ? _messageDeliveryTracker.popPendingDirectMessageId(
+                  contactPublicKey,
+                )
+              : _messageDeliveryTracker.popPendingMessageId();
           if (messageId != null) {
             _messageDeliveryTracker.mapAckTagToMessageId(
               expectedAckTag,
@@ -369,6 +403,9 @@ class ConnectionProvider with ChangeNotifier {
         manufacturerModel: deviceInfo['manufacturerModel'] as String?,
         semanticVersion: deviceInfo['semanticVersion'] as String?,
         clientRepeat: deviceInfo['clientRepeat'] as bool?,
+        supportsSpectrumScan: deviceInfo['supportsSpectrumScan'] as bool?,
+        spectrumScanMinKhz: deviceInfo['spectrumScanMinKhz'] as int?,
+        spectrumScanMaxKhz: deviceInfo['spectrumScanMaxKhz'] as int?,
       );
       notifyListeners();
       if (_sseServer.isRunning) {
@@ -449,10 +486,18 @@ class ConnectionProvider with ChangeNotifier {
   /// Start scanning for MeshCore devices
   Future<void> startScan() async {
     debugPrint('🔍 [Provider] startScan() called');
+    if (_deviceInfo.connectionState == ConnectionState.connecting ||
+        _deviceInfo.connectionState == ConnectionState.connected) {
+      debugPrint(
+        '⏭️ [Provider] Ignoring scan request while connection is active: ${_deviceInfo.connectionState}',
+      );
+      return;
+    }
+
     _isScanning = true;
     _scannedDevices.clear();
     _error = null;
-    notifyListeners();
+    _notifyListenersSafely();
     debugPrint('✅ [Provider] Scan state initialized, notifying listeners');
 
     try {
@@ -468,7 +513,7 @@ class ConnectionProvider with ChangeNotifier {
           debugPrint(
             '✅ [Provider] Added device to list: ${device.platformName} (RSSI: $rssi dBm), total: ${_scannedDevices.length}',
           );
-          notifyListeners();
+          _notifyListenersSafely();
         } else {
           // Update RSSI if device already exists
           final index = _scannedDevices.indexWhere(
@@ -479,7 +524,7 @@ class ConnectionProvider with ChangeNotifier {
             debugPrint(
               '  🔄 [Provider] Updated RSSI for ${device.platformName}: $rssi dBm',
             );
-            notifyListeners();
+            _notifyListenersSafely();
           } else {
             debugPrint(
               '  ⏭️ [Provider] Device already in list with same RSSI, skipping',
@@ -493,7 +538,7 @@ class ConnectionProvider with ChangeNotifier {
     } finally {
       debugPrint('🏁 [Provider] Scan completed');
       _isScanning = false;
-      notifyListeners();
+      _notifyListenersSafely();
     }
   }
 
@@ -501,6 +546,18 @@ class ConnectionProvider with ChangeNotifier {
   Future<void> stopScan() async {
     await FlutterBluePlus.stopScan();
     _isScanning = false;
+    _notifyListenersSafely();
+  }
+
+  void _notifyListenersSafely() {
+    final phase = SchedulerBinding.instance.schedulerPhase;
+    if (phase == SchedulerPhase.transientCallbacks ||
+        phase == SchedulerPhase.persistentCallbacks) {
+      SchedulerBinding.instance.addPostFrameCallback((_) {
+        notifyListeners();
+      });
+      return;
+    }
     notifyListeners();
   }
 
@@ -510,6 +567,11 @@ class ConnectionProvider with ChangeNotifier {
       '🔵 [Provider] connect() called for device: ${device.platformName}',
     );
 
+    if (_isScanning) {
+      debugPrint('🔵 [Provider] Stopping active scan before connect()');
+      await stopScan();
+    }
+
     _deviceInfo = _deviceInfo.copyWith(
       deviceId: device.remoteId.toString(),
       deviceName: device.platformName.isNotEmpty
@@ -558,7 +620,9 @@ class ConnectionProvider with ChangeNotifier {
 
     final success = await _tcpService!.connect(host, port);
     if (!success) {
-      _deviceInfo = _deviceInfo.copyWith(connectionState: ConnectionState.error);
+      _deviceInfo = _deviceInfo.copyWith(
+        connectionState: ConnectionState.error,
+      );
       notifyListeners();
     }
     return success;
@@ -784,10 +848,26 @@ class ConnectionProvider with ChangeNotifier {
       return true;
     } catch (e) {
       debugPrint('❌ [Provider] Failed to check slot $channelIdx: $e');
+      if (_isEmptyChannelQueryError(e)) {
+        debugPrint(
+          '   ℹ️  Treating slot $channelIdx as empty because the device reported it was not found',
+        );
+        return true;
+      }
       return false;
     }
   }
 
+  bool _isEmptyChannelQueryError(Object error) {
+    final message = error.toString().toLowerCase();
+    return message.contains('not found');
+  }
+
+  bool _isChannelRefreshTimeoutError(Object error) {
+    final message = error.toString().toLowerCase();
+    return message.contains('0x1f') && message.contains('timed out');
+  }
+
   Future<int?> findNextEmptyChannelSlot() async {
     if (!_activeService.isConnected) {
       throw Exception('Not connected to device');
@@ -798,6 +878,35 @@ class ConnectionProvider with ChangeNotifier {
 
       // maxChannels from device info, or default to 40
       final maxChannels = _deviceInfo.maxChannels ?? 40;
+      final maxCustomChannels = maxChannels > 0 ? maxChannels - 1 : 0;
+
+      // Match meshcore-open: trust the current synced channel list first and
+      // pick the first missing slot rather than probing every slot on-device.
+      if (getChannelInfo != null) {
+        final usedIndices = <int>{};
+        for (int i = 1; i < maxChannels; i++) {
+          final channel = getChannelInfo!(i);
+          if (channel == null) {
+            continue;
+          }
+
+          final channelName = (channel as dynamic).name as String?;
+          if (channelName != null && channelName.isNotEmpty) {
+            usedIndices.add(i);
+          }
+        }
+
+        for (int i = 1; i < maxChannels; i++) {
+          if (!usedIndices.contains(i)) {
+            debugPrint('   ✅ Found empty slot from synced channels: $i');
+            return i;
+          }
+        }
+
+        debugPrint(
+          '   ⚠️  Synced channels report all custom slots occupied ($maxCustomChannels total)',
+        );
+      }
 
       // Check each slot starting from 1 (skip 0 = public channel)
       for (int i = 1; i < maxChannels; i++) {
@@ -894,10 +1003,12 @@ class ConnectionProvider with ChangeNotifier {
         debugPrint('  Using existing slot: $slotIdx (overwrite mode)');
       } else {
         // Find next empty slot for new channel
+        final maxChannels = _deviceInfo.maxChannels ?? 40;
+        final maxCustomChannels = maxChannels > 0 ? maxChannels - 1 : 0;
         final emptySlot = await findNextEmptyChannelSlot();
         if (emptySlot == null) {
           throw Exception(
-            'All channel slots are in use (maximum 39 custom channels)',
+            'All channel slots are in use (maximum $maxCustomChannels custom channels)',
           );
         }
         slotIdx = emptySlot;
@@ -918,23 +1029,33 @@ class ConnectionProvider with ChangeNotifier {
         debugPrint('  Secret converted to 16-byte key using MD5');
       }
 
-      // Send CMD_SET_CHANNEL to radio
-      await _activeService.setChannel(
-        channelIdx: slotIdx,
-        channelName: channelName,
-        secret: secretBytes,
-      );
+      // Send CMD_SET_CHANNEL to radio. Some devices accept the write but do not
+      // reliably answer the follow-up CMD_GET_CHANNEL verification (0x1F).
+      try {
+        await _activeService.setChannel(
+          channelIdx: slotIdx,
+          channelName: channelName,
+          secret: secretBytes,
+        );
+      } catch (e) {
+        if (_isChannelRefreshTimeoutError(e)) {
+          debugPrint(
+            '⚠️ [Provider] CMD_GET_CHANNEL verification timed out after SET_CHANNEL; assuming the channel write succeeded',
+          );
+          onChannelInfoReceived?.call(
+            slotIdx,
+            channelName,
+            Uint8List.fromList(secretBytes),
+            null,
+          );
+        } else {
+          rethrow;
+        }
+      }
 
       debugPrint(
         '✅ [Provider] Channel ${existingSlot != null ? 'updated' : 'created'} successfully in slot $slotIdx',
       );
-
-      // Small delay to allow the response to propagate
-      await Future.delayed(const Duration(milliseconds: 100));
-
-      // Refresh channels to update UI
-      // The channel info will be received via onChannelInfoReceived callback
-      await _activeService.getChannel(slotIdx);
     } catch (e) {
       _error = 'Failed to create channel: $e';
       debugPrint('❌ [Provider] Channel creation failed: $e');
@@ -1028,7 +1149,7 @@ class ConnectionProvider with ChangeNotifier {
   ///
   /// [messageId] - optional message ID to track delivery status
   /// [contact] - optional contact object for path status logging
-  /// [retryAttempt] - retry attempt number (0 = first send, 1-3 = retries)
+  /// [retryAttempt] - retry attempt number (0 = first send, >0 = retries)
   Future<bool> sendTextMessage({
     required Uint8List contactPublicKey,
     required String text,
@@ -1042,6 +1163,17 @@ class ConnectionProvider with ChangeNotifier {
       return false;
     }
 
+    var effectiveContact = contact;
+    if (messageId != null &&
+        effectiveContact != null &&
+        prepareDirectMessageSendCallback != null) {
+      effectiveContact = await prepareDirectMessageSendCallback!(
+        messageId: messageId,
+        contact: effectiveContact,
+        retryAttempt: retryAttempt,
+      );
+    }
+
     // CRITICAL: Check firmware ACK limit (8 max in circular buffer)
     // Rate limit at 7 to stay under the limit
     if (_messageDeliveryTracker.shouldRateLimit) {
@@ -1066,31 +1198,33 @@ class ConnectionProvider with ChangeNotifier {
 
     try {
       // Log path status and retry info
-      if (contact != null) {
+      if (effectiveContact != null) {
         if (retryAttempt > 0) {
           debugPrint(
-            '🔄 [ConnectionProvider] Sending message to ${contact.advName} (retry $retryAttempt/3)',
+            '🔄 [ConnectionProvider] Sending message to ${effectiveContact.advName} (retry $retryAttempt)',
           );
         } else {
           debugPrint(
-            '📤 [ConnectionProvider] Sending message to ${contact.advName}',
+            '📤 [ConnectionProvider] Sending message to ${effectiveContact.advName}',
           );
         }
-        debugPrint('   Type: ${contact.type.displayName}');
-        debugPrint('   Path status: ${contact.pathDescription}');
-        if (contact.hasPath) {
-          debugPrint('   ✅ Using learned path (${contact.outPathLen} bytes)');
+        debugPrint('   Type: ${effectiveContact.type.displayName}');
+        debugPrint('   Path status: ${effectiveContact.routeSummary}');
+        if (effectiveContact.routeHasPath) {
+          debugPrint(
+            '   ✅ Using learned path (${effectiveContact.routeHopCount} hop(s), ${effectiveContact.routeHashSize}-byte hashes)',
+          );
         } else {
           debugPrint('   ⚠️ No path available - will use flood mode');
         }
       } else if (retryAttempt > 0) {
         debugPrint(
-          '🔄 [ConnectionProvider] Sending message (retry $retryAttempt/3)',
+          '🔄 [ConnectionProvider] Sending message (retry $retryAttempt)',
         );
       }
 
       // Track pending operation for auto-recovery (if contact not found in radio)
-      if (contact != null) {
+      if (effectiveContact != null) {
         final operationId = contactPublicKey
             .sublist(0, 6)
             .map((b) => b.toRadixString(16).padLeft(2, '0'))
@@ -1099,7 +1233,7 @@ class ConnectionProvider with ChangeNotifier {
           contactPublicKey: contactPublicKey,
           text: text,
           messageId: messageId,
-          contact: contact,
+          contact: effectiveContact,
           retryAttempt: retryAttempt,
         );
         debugPrint(
@@ -1115,7 +1249,10 @@ class ConnectionProvider with ChangeNotifier {
       // The MessagesProvider now uses simple ACK tag → recipientPublicKey mapping.
       // We still track here for the SENT response callback to work.
       if (messageId != null) {
-        _messageDeliveryTracker.trackPendingMessage(messageId);
+        _messageDeliveryTracker.trackPendingDirectMessage(
+          messageId,
+          contactPublicKey,
+        );
         debugPrint('  📝 Tracked pending message: $messageId');
       }
 
@@ -1126,9 +1263,22 @@ class ConnectionProvider with ChangeNotifier {
         attempt: retryAttempt,
       );
 
+      if (messageId != null) {
+        Future.delayed(const Duration(milliseconds: 350), () {
+          if (_messageDeliveryTracker.hasAckForMessage(messageId)) {
+            return;
+          }
+
+          debugPrint(
+            'ℹ️ [ConnectionProvider] Missing RESP_CODE_SENT for $messageId; promoting to sent via fallback',
+          );
+          onMessageSent?.call(messageId, 0, 0);
+        });
+      }
+
       // Clear pending operation after successful send (no error)
       // If ERR_CODE_NOT_FOUND occurs, the operation will be recovered automatically
-      if (contact != null) {
+      if (effectiveContact != null) {
         final operationId = contactPublicKey
             .sublist(0, 6)
             .map((b) => b.toRadixString(16).padLeft(2, '0'))
@@ -1169,7 +1319,10 @@ class ConnectionProvider with ChangeNotifier {
       debugPrint('  Text: $text');
       debugPrint('  MessageID: $messageId');
 
-      await _activeService.sendChannelMessage(channelIdx: channelIdx, text: text);
+      await _activeService.sendChannelMessage(
+        channelIdx: channelIdx,
+        text: text,
+      );
 
       debugPrint('✅ [ConnectionProvider] BLE send completed');
       debugPrint(
@@ -1224,6 +1377,19 @@ class ConnectionProvider with ChangeNotifier {
     );
   }
 
+  /// Send a raw private zero-hop payload.
+  ///
+  /// This wraps the raw custom transport using an empty path to match the
+  /// firmware's private multicast behavior.
+  Future<void> sendRawPrivateMulticast(Uint8List payload) async {
+    if (!_activeService.isConnected) return;
+    await _activeService.sendRawVoicePacket(
+      contactPathLen: 0,
+      contactPath: Uint8List(0),
+      payload: payload,
+    );
+  }
+
   /// Request telemetry from contact
   ///
   /// COMPATIBILITY NOTE: This method sends CMD_SEND_TELEMETRY_REQ (39).
@@ -1270,6 +1436,34 @@ class ConnectionProvider with ChangeNotifier {
     required Uint8List contactPublicKey,
     required bool hasPath,
     Function()? onRetryWithFlooding,
+  }) async {
+    final pingKey = _publicKeyToHex(contactPublicKey);
+    final pendingPing = _pendingSmartPings[pingKey];
+    if (pendingPing != null) {
+      debugPrint('ℹ️ [Provider] Joining in-flight ping for $pingKey');
+      return pendingPing;
+    }
+
+    final future = _runSmartPing(
+      contactPublicKey: contactPublicKey,
+      hasPath: hasPath,
+      onRetryWithFlooding: onRetryWithFlooding,
+    );
+    _pendingSmartPings[pingKey] = future;
+    notifyListeners();
+
+    try {
+      return await future;
+    } finally {
+      _pendingSmartPings.remove(pingKey);
+      notifyListeners();
+    }
+  }
+
+  Future<PingResult> _runSmartPing({
+    required Uint8List contactPublicKey,
+    required bool hasPath,
+    Function()? onRetryWithFlooding,
   }) async {
     if (!_activeService.isConnected) {
       _error = 'Not connected to device';
@@ -1288,7 +1482,10 @@ class ConnectionProvider with ChangeNotifier {
       );
 
       // Send the ping
-      await _activeService.requestTelemetry(contactPublicKey, zeroHop: true);
+      await _activeService.requestTelemetry(
+        contactPublicKey,
+        zeroHop: firstAttemptDirect,
+      );
 
       // Wait for response or timeout
       final bool gotResponse = await pingFuture;
@@ -1315,8 +1512,8 @@ class ConnectionProvider with ChangeNotifier {
           wasDirectAttempt: false,
         );
 
-        // Retry with flooding (zeroHop=true acts as broadcast to neighbors)
-        await _activeService.requestTelemetry(contactPublicKey, zeroHop: true);
+        // Retry with flooding.
+        await _activeService.requestTelemetry(contactPublicKey, zeroHop: false);
 
         // Wait for response or timeout
         final bool gotRetryResponse = await retryFuture;
@@ -1338,6 +1535,10 @@ class ConnectionProvider with ChangeNotifier {
     }
   }
 
+  String _publicKeyToHex(Uint8List publicKey) {
+    return publicKey.map((b) => b.toRadixString(16).padLeft(2, '0')).join('');
+  }
+
   /// Send binary request to contact (modern replacement for requestTelemetry)
   ///
   /// Supports multiple request types:
@@ -1528,6 +1729,43 @@ class ConnectionProvider with ChangeNotifier {
     }
   }
 
+  Future<SpectrumScanResult?> scanSpectrum({
+    required int startFrequencyKhz,
+    required int stopFrequencyKhz,
+    required int bandwidthKhz,
+    required int stepKhz,
+    required int dwellMs,
+    required int thresholdDb,
+  }) async {
+    if (!_activeService.isConnected) {
+      _error = 'Not connected to device';
+      notifyListeners();
+      return null;
+    }
+
+    try {
+      _isSpectrumScanActive = true;
+      _activeService.setSpectrumScanActive(true);
+      notifyListeners();
+      return await _activeService.scanSpectrum(
+        startFrequencyKhz: startFrequencyKhz,
+        stopFrequencyKhz: stopFrequencyKhz,
+        bandwidthKhz: bandwidthKhz,
+        stepKhz: stepKhz,
+        dwellMs: dwellMs,
+        thresholdDb: thresholdDb,
+      );
+    } catch (e) {
+      _error = 'Failed to scan spectrum: $e';
+      notifyListeners();
+      return null;
+    } finally {
+      _isSpectrumScanActive = false;
+      _activeService.setSpectrumScanActive(false);
+      notifyListeners();
+    }
+  }
+
   /// Set transmit power
   Future<void> setTxPower(int powerDbm) async {
     if (!_activeService.isConnected) {
@@ -1572,6 +1810,7 @@ class ConnectionProvider with ChangeNotifier {
 
   /// Request fresh device info (triggers SelfInfo response)
   Future<void> refreshDeviceInfo() async {
+    if (_isSpectrumScanActive) return;
     if (!_activeService.isConnected) {
       _error = 'Not connected to device';
       notifyListeners();
@@ -1615,6 +1854,7 @@ class ConnectionProvider with ChangeNotifier {
   /// Sync messages from device queue
   /// Call this repeatedly until no more messages are available
   Future<bool> syncNextMessage() async {
+    if (_isSpectrumScanActive) return false;
     // Prevent re-entrancy and too-fast triggers
     if (_isSyncingMessages) {
       // Another sync (single or loop) is in progress
@@ -1653,8 +1893,13 @@ class ConnectionProvider with ChangeNotifier {
 
   /// Sync all waiting messages from device
   Future<int> syncAllMessages() async {
+    if (_isSpectrumScanActive) {
+      debugPrint('⏸️ [Provider] Message sync skipped during spectrum scan');
+      return 0;
+    }
     if (_isSyncingMessages) {
       // Already syncing; avoid overlapping loops
+      _syncRequestedWhileBusy = true;
       return 0;
     }
 
@@ -1664,83 +1909,94 @@ class ConnectionProvider with ChangeNotifier {
       return 0;
     }
 
-    int count = 0;
-    _noMoreMessages = false; // Reset flag
+    int totalCount = 0;
 
     try {
       _isSyncingMessages = true;
-      debugPrint('🔄 [Provider] Starting message sync loop...');
-      debugPrint('  Initial _noMoreMessages state: $_noMoreMessages');
+      do {
+        _syncRequestedWhileBusy = false;
+        _noMoreMessages = false; // Reset flag per pass
+        int passCount = 0;
+        debugPrint('🔄 [Provider] Starting message sync loop...');
+        debugPrint('  Initial _noMoreMessages state: $_noMoreMessages');
+
+        // Keep syncing until we get NoMoreMessages response
+        // The device will send ContactMsgRecv or ChannelMsgRecv responses
+        // until it sends NoMoreMessages
+        for (int i = 0; i < 100; i++) {
+          // Safety limit
+          // Check flag BEFORE sending (not after)
+          if (_noMoreMessages) {
+            debugPrint(
+              '✅ [Provider] Message sync complete - NoMoreMessages flag set after $passCount requests',
+            );
+            break;
+          }
 
-      // Keep syncing until we get NoMoreMessages response
-      // The device will send ContactMsgRecv or ChannelMsgRecv responses
-      // until it sends NoMoreMessages
-      for (int i = 0; i < 100; i++) {
-        // Safety limit
-        // Check flag BEFORE sending (not after)
-        if (_noMoreMessages) {
           debugPrint(
-            '✅ [Provider] Message sync complete - NoMoreMessages flag set after $count requests',
+            '📤 [Provider] Sync iteration ${i + 1}: Sending CMD_SYNC_NEXT_MESSAGE',
           );
-          break;
-        }
 
-        debugPrint(
-          '📤 [Provider] Sync iteration ${i + 1}: Sending CMD_SYNC_NEXT_MESSAGE',
-        );
+          // Create new completer for this request
+          _syncResponseCompleter = Completer<bool>();
 
-        // Create new completer for this request
-        _syncResponseCompleter = Completer<bool>();
+          // Respect the minimum interval between requests
+          final now = DateTime.now();
+          if (_lastSyncNextRequestedAt != null) {
+            final elapsed = now.difference(_lastSyncNextRequestedAt!);
+            if (elapsed < _minSyncNextInterval) {
+              final remaining = _minSyncNextInterval - elapsed;
+              await Future.delayed(remaining);
+            }
+          }
 
-        // Respect the minimum interval between requests
-        final now = DateTime.now();
-        if (_lastSyncNextRequestedAt != null) {
-          final elapsed = now.difference(_lastSyncNextRequestedAt!);
-          if (elapsed < _minSyncNextInterval) {
-            final remaining = _minSyncNextInterval - elapsed;
-            await Future.delayed(remaining);
+          await _activeService.syncNextMessage();
+          _lastSyncNextRequestedAt = DateTime.now();
+          passCount++;
+          totalCount++;
+
+          // Wait for response (true = message received, false = no more messages)
+          // Timeout after 2 seconds to prevent hanging
+          final hasMore = await _syncResponseCompleter!.future.timeout(
+            const Duration(seconds: 2),
+            onTimeout: () {
+              debugPrint('⚠️ [Provider] Sync timeout - no response after 2s');
+              return false;
+            },
+          );
+
+          debugPrint(
+            '  After iteration ${i + 1}: hasMore=$hasMore, _noMoreMessages=$_noMoreMessages',
+          );
+
+          if (!hasMore) {
+            debugPrint('  ✅ No more messages available, stopping sync');
+            break;
           }
         }
 
-        await _activeService.syncNextMessage();
-        _lastSyncNextRequestedAt = DateTime.now();
-        count++;
-
-        // Wait for response (true = message received, false = no more messages)
-        // Timeout after 2 seconds to prevent hanging
-        final hasMore = await _syncResponseCompleter!.future.timeout(
-          const Duration(seconds: 2),
-          onTimeout: () {
-            debugPrint('⚠️ [Provider] Sync timeout - no response after 2s');
-            return false;
-          },
-        );
-
-        debugPrint(
-          '  After iteration ${i + 1}: hasMore=$hasMore, _noMoreMessages=$_noMoreMessages',
-        );
-
-        if (!hasMore) {
-          debugPrint('  ✅ No more messages available, stopping sync');
-          break;
+        if (!_noMoreMessages && passCount >= 100) {
+          debugPrint(
+            '⚠️ [Provider] Message sync stopped - reached safety limit of 100 requests without NoMoreMessages',
+          );
         }
-      }
 
-      if (!_noMoreMessages && count >= 100) {
-        debugPrint(
-          '⚠️ [Provider] Message sync stopped - reached safety limit of 100 requests without NoMoreMessages',
-        );
-      }
+        if (_syncRequestedWhileBusy) {
+          debugPrint(
+            '↻ [Provider] MSG_WAITING received during sync; running another pass',
+          );
+        }
+      } while (_syncRequestedWhileBusy && _activeService.isConnected);
 
       debugPrint(
-        '🏁 [Provider] Message sync finished: sent $count sync requests, _noMoreMessages=$_noMoreMessages',
+        '🏁 [Provider] Message sync finished: sent $totalCount sync requests, _noMoreMessages=$_noMoreMessages',
       );
-      return count;
+      return totalCount;
     } catch (e) {
       debugPrint('❌ [Provider] Failed to sync messages: $e');
       _error = 'Failed to sync messages: $e';
       notifyListeners();
-      return count;
+      return totalCount;
     } finally {
       _isSyncingMessages = false;
       _syncResponseCompleter = null;
@@ -1859,6 +2115,7 @@ class ConnectionProvider with ChangeNotifier {
     }
 
     try {
+      _error = null;
       await _activeService.resetPath(contactPublicKey);
     } catch (e) {
       _error = 'Failed to reset path: $e';
@@ -1866,6 +2123,31 @@ class ConnectionProvider with ChangeNotifier {
     }
   }
 
+  Future<void> setContactRoute(
+    Contact contact, {
+    required int signedEncodedPathLen,
+    required Uint8List paddedPathBytes,
+  }) async {
+    if (!_activeService.isConnected) {
+      _error = 'Not connected to device';
+      notifyListeners();
+      return;
+    }
+
+    try {
+      _error = null;
+      final updatedContact = contact.copyWith(
+        outPathLen: signedEncodedPathLen,
+        outPath: Uint8List.fromList(paddedPathBytes),
+      );
+      await _activeService.addOrUpdateContact(updatedContact);
+    } catch (e) {
+      _error = 'Failed to set route: $e';
+      notifyListeners();
+      rethrow;
+    }
+  }
+
   /// Remove a contact from the companion radio
   ///
   /// Deletes the contact from the device's internal contact table.

lib/providers/contacts_provider.dart

@@ -1,8 +1,10 @@
 import 'package:flutter/foundation.dart';
 import 'package:latlong2/latlong.dart';
 import '../models/contact.dart';
+import '../models/message_contact_location.dart';
 import '../services/cayenne_lpp_parser.dart';
 import '../services/contact_storage_service.dart';
+import '../utils/fast_gps_packet.dart';
 import '../utils/key_comparison.dart';
 
 class PendingAdvert {
@@ -214,6 +216,52 @@ class ContactsProvider with ChangeNotifier {
   List<Contact> get chatContactsWithLocation =>
       chatContacts.where((c) => c.displayLocation != null).toList();
 
+  MessageContactLocation? buildMessageContactLocationSnapshot(
+    Contact contact, {
+    DateTime? capturedAt,
+  }) {
+    final snapshotTime = capturedAt ?? DateTime.now();
+    final telemetryGps = _getValidGpsOrNull(contact.telemetry?.gpsLocation);
+    final telemetryTimestamp = contact.telemetry?.timestamp;
+
+    AdvertLocation? advertLocation;
+    for (final point in contact.advertHistory) {
+      if (!point.timestamp.isAfter(snapshotTime)) {
+        advertLocation = point;
+        break;
+      }
+    }
+    advertLocation ??= contact.advertHistory.isNotEmpty
+        ? contact.advertHistory.first
+        : null;
+
+    if (telemetryGps != null) {
+      final shouldUseTelemetry =
+          telemetryTimestamp == null ||
+          advertLocation == null ||
+          !telemetryTimestamp.isBefore(advertLocation.timestamp);
+      if (shouldUseTelemetry) {
+        return MessageContactLocation(
+          location: telemetryGps,
+          source: 'telemetry',
+          capturedAt: snapshotTime,
+          sourceTimestamp: telemetryTimestamp,
+        );
+      }
+    }
+
+    if (advertLocation != null) {
+      return MessageContactLocation(
+        location: advertLocation.location,
+        source: 'advert',
+        capturedAt: snapshotTime,
+        sourceTimestamp: advertLocation.timestamp,
+      );
+    }
+
+    return null;
+  }
+
   /// Sort contacts by last seen (most recent first)
   int _sortByLastSeen(Contact a, Contact b) {
     return b.lastSeenTime.compareTo(a.lastSeenTime);
@@ -235,45 +283,16 @@ class ContactsProvider with ChangeNotifier {
     }
 
     // Check if this is a new contact
-    final isNewContact = !_contacts.containsKey(contact.publicKeyHex);
+    final existingContact = _contacts[contact.publicKeyHex];
+    final isNewContact = existingContact == null;
     debugPrint(
       '   isNew: $isNewContact, total contacts before: ${_contacts.length}',
     );
 
-    Contact updatedContact;
-    if (isNewContact) {
-      // New contact - add initial location to history if available
-      updatedContact = contact.copyWith(isNew: true);
-      if (contact.advertLocation != null) {
-        final timestamp = DateTime.fromMillisecondsSinceEpoch(
-          contact.lastAdvert * 1000,
-        );
-        updatedContact = updatedContact.addAdvertLocation(
-          contact.advertLocation!,
-          timestamp,
-        );
-      }
-    } else {
-      // Existing contact - preserve history and isNew status
-      final existingContact = _contacts[contact.publicKeyHex]!;
-
-      // Start with existing contact
-      updatedContact = contact.copyWith(
-        isNew: existingContact.isNew,
-        advertHistory: existingContact.advertHistory,
-      );
-
-      // Add new location to history if location has changed
-      if (contact.advertLocation != null) {
-        final timestamp = DateTime.fromMillisecondsSinceEpoch(
-          contact.lastAdvert * 1000,
-        );
-        updatedContact = updatedContact.addAdvertLocation(
-          contact.advertLocation!,
-          timestamp,
-        );
-      }
-    }
+    final updatedContact = _mergeIncomingContact(
+      incomingContact: contact,
+      existingContact: existingContact,
+    );
 
     _contacts[contact.publicKeyHex] = updatedContact;
     _pendingAdverts.remove(contact.publicKeyHex);
@@ -299,7 +318,11 @@ class ContactsProvider with ChangeNotifier {
         excluded++;
         continue;
       }
-      _contacts[contact.publicKeyHex] = contact;
+      final existingContact = _contacts[contact.publicKeyHex];
+      _contacts[contact.publicKeyHex] = _mergeIncomingContact(
+        incomingContact: contact,
+        existingContact: existingContact,
+      );
       _pendingAdverts.remove(contact.publicKeyHex);
     }
     if (excluded > 0) {
@@ -311,6 +334,60 @@ class ContactsProvider with ChangeNotifier {
     notifyListeners();
   }
 
+  Contact _mergeIncomingContact({
+    required Contact incomingContact,
+    Contact? existingContact,
+  }) {
+    if (existingContact == null) {
+      var newContact = incomingContact.copyWith(isNew: true);
+      if (incomingContact.advertLocation != null) {
+        final timestamp = DateTime.fromMillisecondsSinceEpoch(
+          incomingContact.lastAdvert * 1000,
+        );
+        newContact = newContact.addAdvertLocation(
+          incomingContact.advertLocation!,
+          timestamp,
+        );
+      }
+      return newContact;
+    }
+
+    final mergedTelemetry = _mergeTelemetryForContact(
+      existingTelemetry: existingContact.telemetry,
+      incomingTelemetry: incomingContact.telemetry,
+    );
+    final incomingAdvertLocation = incomingContact.advertLocation;
+    final existingAdvertLocation = existingContact.advertLocation;
+
+    var updatedContact = incomingContact.copyWith(
+      isNew: existingContact.isNew,
+      advertHistory: existingContact.advertHistory,
+      telemetry: mergedTelemetry,
+      advLat: incomingAdvertLocation != null
+          ? incomingContact.advLat
+          : existingAdvertLocation != null
+          ? existingContact.advLat
+          : incomingContact.advLat,
+      advLon: incomingAdvertLocation != null
+          ? incomingContact.advLon
+          : existingAdvertLocation != null
+          ? existingContact.advLon
+          : incomingContact.advLon,
+    );
+
+    if (incomingAdvertLocation != null) {
+      final timestamp = DateTime.fromMillisecondsSinceEpoch(
+        incomingContact.lastAdvert * 1000,
+      );
+      updatedContact = updatedContact.addAdvertLocation(
+        incomingAdvertLocation,
+        timestamp,
+      );
+    }
+
+    return updatedContact;
+  }
+
   /// Update contact telemetry
   void updateTelemetry(Uint8List publicKeyPrefix, Uint8List lppData) {
     debugPrint('📊 [ContactsProvider] updateTelemetry() called');
@@ -350,23 +427,22 @@ class ContactsProvider with ChangeNotifier {
         );
       }
 
-      // Keep last valid GPS for router/chat/room contacts when current
-      // telemetry does not provide a valid GPS fix.
-      if (_shouldRetainLastValidGps(contact, telemetry.gpsLocation)) {
-        debugPrint(
-          '  ⚠️ Retaining last valid GPS. Incoming telemetry GPS is invalid/missing: $incomingGps',
-        );
-        final previousGps = _getValidGpsOrNull(contact.telemetry?.gpsLocation);
-        telemetry = ContactTelemetry(
-          gpsLocation: previousGps,
-          batteryPercentage: telemetry.batteryPercentage,
-          batteryMilliVolts: telemetry.batteryMilliVolts,
-          temperature: telemetry.temperature,
-          timestamp: telemetry.timestamp,
-          humidity: telemetry.humidity,
-          pressure: telemetry.pressure,
-          extraSensorData: telemetry.extraSensorData,
-        );
+      final previousTelemetry = contact.telemetry;
+
+      final mergedTelemetry = _mergeTelemetryForContact(
+        existingTelemetry: previousTelemetry,
+        incomingTelemetry: telemetry,
+      );
+      if (mergedTelemetry != null) {
+        if (_shouldRetainLastValidGps(
+          previousTelemetry,
+          telemetry.gpsLocation,
+        )) {
+          debugPrint(
+            '  ⚠️ Retaining last valid GPS. Incoming telemetry GPS is invalid/missing: $incomingGps',
+          );
+        }
+        telemetry = mergedTelemetry;
       }
 
       // Update contact with new telemetry AND last seen time
@@ -376,9 +452,16 @@ class ContactsProvider with ChangeNotifier {
       debugPrint('  Old lastAdvert: ${contact.lastAdvert}');
       debugPrint('  New lastAdvert: $currentTimestamp');
 
+      final persistedGps = _getValidGpsOrNull(telemetry.gpsLocation);
       final updatedContact = contact.copyWith(
         telemetry: telemetry,
         lastAdvert: currentTimestamp, // Update last seen time
+        advLat: persistedGps != null
+            ? _coordinateToAdvertMicrodegrees(persistedGps.latitude)
+            : contact.advLat,
+        advLon: persistedGps != null
+            ? _coordinateToAdvertMicrodegrees(persistedGps.longitude)
+            : contact.advLon,
       );
       _contacts[contact.publicKeyHex] = updatedContact;
       debugPrint('  ✅ Updated contact in map (with new lastAdvert)');
@@ -394,6 +477,42 @@ class ContactsProvider with ChangeNotifier {
     }
   }
 
+  void updateFastGps(Uint8List publicKeyPrefix, FastGpsPacket packet) {
+    final contact = _findContactByPrefix(publicKeyPrefix);
+    if (contact == null) {
+      debugPrint(
+        '⚠️ [ContactsProvider] Fast GPS sender not found: ${packet.senderKey6}',
+      );
+      return;
+    }
+
+    final updatedTelemetry = _mergeTelemetryForContact(
+      existingTelemetry: contact.telemetry,
+      incomingTelemetry: ContactTelemetry(
+        gpsLocation: LatLng(packet.latitude, packet.longitude),
+        batteryPercentage: null,
+        batteryMilliVolts: null,
+        temperature: null,
+        timestamp: DateTime.fromMillisecondsSinceEpoch(
+          packet.timestampSeconds * 1000,
+        ),
+        humidity: null,
+        pressure: null,
+        extraSensorData: null,
+      ),
+    );
+
+    final updatedContact = contact.copyWith(
+      telemetry: updatedTelemetry,
+      lastAdvert: packet.timestampSeconds,
+      advLat: _coordinateToAdvertMicrodegrees(packet.latitude),
+      advLon: _coordinateToAdvertMicrodegrees(packet.longitude),
+    );
+    _contacts[contact.publicKeyHex] = updatedContact;
+    _persistContacts();
+    notifyListeners();
+  }
+
   bool _isInvalidTelemetryGps(LatLng? location) {
     if (location == null) return false;
     final lat = location.latitude;
@@ -413,15 +532,12 @@ class ContactsProvider with ChangeNotifier {
     return location;
   }
 
-  bool _shouldRetainLastValidGps(Contact contact, LatLng? incomingGps) {
-    final isSupportedType =
-        contact.isChat || contact.isRepeater || contact.isRoom;
-    if (!isSupportedType) {
-      return false;
-    }
-
+  bool _shouldRetainLastValidGps(
+    ContactTelemetry? existingTelemetry,
+    LatLng? incomingGps,
+  ) {
     final hasPreviousValidGps =
-        _getValidGpsOrNull(contact.telemetry?.gpsLocation) != null;
+        _getValidGpsOrNull(existingTelemetry?.gpsLocation) != null;
     if (!hasPreviousValidGps) {
       return false;
     }
@@ -429,6 +545,46 @@ class ContactsProvider with ChangeNotifier {
     return incomingGps == null;
   }
 
+  ContactTelemetry? _mergeTelemetryForContact({
+    ContactTelemetry? existingTelemetry,
+    ContactTelemetry? incomingTelemetry,
+  }) {
+    if (incomingTelemetry == null) {
+      return existingTelemetry;
+    }
+
+    // Telemetry packets and contact refreshes are often sparse. Preserve the
+    // last known reading for any field that is omitted in the incoming update.
+    final incomingGps = _getValidGpsOrNull(incomingTelemetry.gpsLocation);
+    final previousGps = _getValidGpsOrNull(existingTelemetry?.gpsLocation);
+    final mergedExtraSensorData = <String, dynamic>{
+      ...?existingTelemetry?.extraSensorData,
+      ...?incomingTelemetry.extraSensorData,
+    };
+
+    return ContactTelemetry(
+      gpsLocation: incomingGps ?? previousGps,
+      batteryPercentage:
+          incomingTelemetry.batteryPercentage ??
+          existingTelemetry?.batteryPercentage,
+      batteryMilliVolts:
+          incomingTelemetry.batteryMilliVolts ??
+          existingTelemetry?.batteryMilliVolts,
+      temperature:
+          incomingTelemetry.temperature ?? existingTelemetry?.temperature,
+      timestamp: incomingTelemetry.timestamp,
+      humidity: incomingTelemetry.humidity ?? existingTelemetry?.humidity,
+      pressure: incomingTelemetry.pressure ?? existingTelemetry?.pressure,
+      extraSensorData: mergedExtraSensorData.isEmpty
+          ? null
+          : mergedExtraSensorData,
+    );
+  }
+
+  int _coordinateToAdvertMicrodegrees(double coordinate) {
+    return (coordinate * 1e6).round();
+  }
+
   /// Find contact by public key prefix (6 bytes)
   Contact? _findContactByPrefix(Uint8List prefix) {
     if (prefix.length < 6) return null;
@@ -470,6 +626,54 @@ class ContactsProvider with ChangeNotifier {
     return _contacts[keyHex];
   }
 
+  /// Clear a contact's learned path locally so the UI and next send both
+  /// prefer flood routing until the radio reports a fresh route.
+  void markPathUnhealthy(Uint8List publicKey) {
+    final contact = findContactByKey(publicKey);
+    if (contact == null || !contact.routeHasPath) {
+      return;
+    }
+
+    _contacts[contact.publicKeyHex] = contact.copyWith(
+      outPathLen: -1,
+      outPath: Uint8List(0),
+    );
+    _persistContacts();
+    notifyListeners();
+  }
+
+  void setContactRouteLocal(
+    Uint8List publicKey, {
+    required int signedEncodedPathLen,
+    required Uint8List paddedPathBytes,
+  }) {
+    final contact = findContactByKey(publicKey);
+    if (contact == null) {
+      return;
+    }
+
+    _contacts[contact.publicKeyHex] = contact.copyWith(
+      outPathLen: signedEncodedPathLen,
+      outPath: Uint8List.fromList(paddedPathBytes),
+    );
+    _persistContacts();
+    notifyListeners();
+  }
+
+  void resetContactRouteLocal(Uint8List publicKey) {
+    final contact = findContactByKey(publicKey);
+    if (contact == null) {
+      return;
+    }
+
+    _contacts[contact.publicKeyHex] = contact.copyWith(
+      outPathLen: -1,
+      outPath: Uint8List(0),
+    );
+    _persistContacts();
+    notifyListeners();
+  }
+
   /// Add or refresh a pending advert entry from PUSH_CODE_ADVERT (0x80).
   /// Excludes self key and existing contacts.
   void addPendingAdvert(Uint8List publicKey, {Uint8List? devicePublicKey}) {

lib/providers/helpers/fragment_ack_wait_registry.dart

@@ -0,0 +1,43 @@
+import 'dart:async';
+
+/// Tracks one or more in-flight waiters for the same fragment ACK key.
+///
+/// Duplicate fetch requests can race and wait on the same fragment ACK at once.
+/// Completing all registered waiters avoids losing the earlier completer when a
+/// later request registers for the same key.
+class FragmentAckWaitRegistry {
+  final Map<String, List<Completer<void>>> _waiters = {};
+
+  Future<bool> waitFor(
+    String key, {
+    Duration timeout = const Duration(seconds: 8),
+  }) async {
+    final completer = Completer<void>();
+    final waiters = _waiters.putIfAbsent(key, () => <Completer<void>>[]);
+    waiters.add(completer);
+    try {
+      await completer.future.timeout(timeout);
+      return true;
+    } catch (_) {
+      final pending = _waiters[key];
+      pending?.remove(completer);
+      if (pending != null && pending.isEmpty) {
+        _waiters.remove(key);
+      }
+      return false;
+    }
+  }
+
+  int complete(String key) {
+    final waiters = _waiters.remove(key);
+    if (waiters == null || waiters.isEmpty) {
+      return 0;
+    }
+    for (final completer in waiters) {
+      if (!completer.isCompleted) {
+        completer.complete();
+      }
+    }
+    return waiters.length;
+  }
+}

lib/providers/helpers/message_delivery_tracker.dart

@@ -1,3 +1,5 @@
+import 'dart:typed_data';
+
 /// Message delivery tracking helper
 ///
 /// Manages message delivery tracking for sent messages, including:
@@ -16,6 +18,9 @@ class MessageDeliveryTracker {
   /// Messages tracked here before sending, popped when RESP_CODE_SENT arrives
   final List<String> _pendingMessageIds = [];
 
+  /// Contact-scoped FIFOs for matching direct-message SENT responses.
+  final Map<String, List<String>> _pendingMessageIdsByContact = {};
+
   /// Map of ACK tag to message ID for delivery confirmation
   final Map<int, String> _ackTagToMessageId = {};
 
@@ -33,6 +38,15 @@ class MessageDeliveryTracker {
     _pendingMessageIds.add(messageId);
   }
 
+  /// Track a pending direct message ID for a specific contact.
+  void trackPendingDirectMessage(String messageId, Uint8List contactPublicKey) {
+    trackPendingMessage(messageId);
+    final contactKey = _contactKey(contactPublicKey);
+    _pendingMessageIdsByContact
+        .putIfAbsent(contactKey, () => [])
+        .add(messageId);
+  }
+
   /// Pop the next pending message ID from FIFO queue
   ///
   /// Called when RESP_CODE_SENT arrives. Returns null if queue empty.
@@ -43,6 +57,24 @@ class MessageDeliveryTracker {
     return _pendingMessageIds.removeAt(0);
   }
 
+  /// Pop the next pending direct message ID for a specific contact.
+  ///
+  /// Falls back to the legacy global FIFO if the contact queue is empty.
+  String? popPendingDirectMessageId(Uint8List contactPublicKey) {
+    final contactKey = _contactKey(contactPublicKey);
+    final queue = _pendingMessageIdsByContact[contactKey];
+    if (queue == null || queue.isEmpty) {
+      return popPendingMessageId();
+    }
+
+    final messageId = queue.removeAt(0);
+    if (queue.isEmpty) {
+      _pendingMessageIdsByContact.remove(contactKey);
+    }
+    _pendingMessageIds.remove(messageId);
+    return messageId;
+  }
+
   /// Map ACK tag to message ID after RESP_CODE_SENT received
   ///
   /// Creates bidirectional mapping for efficient cleanup and tracking.
@@ -66,6 +98,11 @@ class MessageDeliveryTracker {
     return _ackTagToMessageId[ackCode];
   }
 
+  /// Returns true once a message has been matched to a concrete ACK tag.
+  bool hasAckForMessage(String messageId) {
+    return _messageIdToAckTag.containsKey(messageId);
+  }
+
   /// Remove ACK tag mapping after delivery confirmed or timeout
   ///
   /// Cleans up both forward and reverse mappings.
@@ -86,6 +123,17 @@ class MessageDeliveryTracker {
       _ackTagToMessageId.remove(ackTag);
       _ackTagTimestamps.remove(ackTag);
     }
+    _pendingMessageIds.remove(messageId);
+    final emptyKeys = <String>[];
+    for (final entry in _pendingMessageIdsByContact.entries) {
+      entry.value.remove(messageId);
+      if (entry.value.isEmpty) {
+        emptyKeys.add(entry.key);
+      }
+    }
+    for (final key in emptyKeys) {
+      _pendingMessageIdsByContact.remove(key);
+    }
   }
 
   /// Clean up stale ACK mappings
@@ -114,6 +162,7 @@ class MessageDeliveryTracker {
   /// Clear all tracking state
   void clearTracking() {
     _pendingMessageIds.clear();
+    _pendingMessageIdsByContact.clear();
     _ackTagToMessageId.clear();
     _messageIdToAckTag.clear();
     _ackTagTimestamps.clear();
@@ -133,9 +182,7 @@ class MessageDeliveryTracker {
   /// Get oldest pending ACK timestamp (for debugging)
   DateTime? get oldestPendingTimestamp {
     if (_ackTagTimestamps.isEmpty) return null;
-    return _ackTagTimestamps.values.reduce(
-      (a, b) => a.isBefore(b) ? a : b,
-    );
+    return _ackTagTimestamps.values.reduce((a, b) => a.isBefore(b) ? a : b);
   }
 
   /// Get diagnostic info for debugging
@@ -145,6 +192,15 @@ class MessageDeliveryTracker {
       'shouldRateLimit': shouldRateLimit,
       'oldestPending': oldestPendingTimestamp?.toIso8601String(),
       'ackTags': _ackTagToMessageId.keys.toList(),
+      'pendingByContact': _pendingMessageIdsByContact.map(
+        (key, value) => MapEntry(key, value.length),
+      ),
     };
   }
+
+  String _contactKey(Uint8List contactPublicKey) {
+    return contactPublicKey
+        .map((b) => b.toRadixString(16).padLeft(2, '0'))
+        .join();
+  }
 }

lib/providers/helpers/message_retry_manager.dart

@@ -1,74 +1,69 @@
+import 'dart:convert';
+
 import '../../models/message.dart';
 import '../../models/contact.dart';
 
 /// Manages message retry state and logic
 ///
-/// This helper class centralizes retry logic for direct messages, implementing
-/// a progressive timeout strategy (4s, 8s, 12s) for messages sent to contacts
-/// with learned routing paths.
+/// This helper class centralizes retry logic for direct messages.
 ///
 /// IMPORTANT: Based on MeshCore firmware analysis:
 /// - Firmware calculates timeout based on path length and airtime
 /// - Direct mode: ~(path_len * airtime * 2) + margin
 /// - Flood mode: ~10-30 seconds for multi-hop
-/// - Our timeouts (4s, 8s, 12s) are conservative for direct paths
+/// - Our retry delays (1s, 2s, 4s, 8s) are app-level backoff timers
 /// - Firmware does NOT automatically retry - app must implement
 class MessageRetryManager {
   // Track retry state for each message ID
   final Map<String, int> _retryAttempts = {};
   final Map<String, DateTime> _lastRetryTimes = {};
+  final Map<String, int> _pathFailureStreaks = {};
 
-  // Progressive timeout values in milliseconds
-  // These are app-level timeouts, separate from firmware's suggested timeout
-  // Firmware timeout is for ACK arrival, these are for retry attempts
-  static const List<int> _timeouts = [4000, 8000, 12000];
+  static const int maxRetryAttempts = 4;
 
-  /// Get timeout for a specific retry attempt (0-2)
-  /// Returns: 4000ms for attempt 0, 8000ms for attempt 1, 12000ms for attempt 2
-  int getTimeoutForAttempt(int attempt) {
-    if (attempt < 0 || attempt >= _timeouts.length) {
-      return _timeouts.last; // Default to last timeout if out of range
+  // Retry backoff values in milliseconds.
+  static const List<int> _retryDelays = [1000, 2000, 4000, 8000];
+  static const int _defaultLoRaSf = 10;
+  static const int _defaultLoRaCr = 5;
+  static const int _defaultLoRaBwHz = 250000;
+  static const int _defaultLoRaPreambleSymbols = 8;
+  static const int _defaultLoRaCrcEnabled = 1;
+  static const int _defaultLoRaExplicitHeader = 1;
+
+  /// Get backoff delay for the next retry attempt.
+  int getDelayForAttempt(int attempt) {
+    if (attempt < 0 || attempt >= _retryDelays.length) {
+      return _retryDelays.last;
     }
-    return _timeouts[attempt];
+    return _retryDelays[attempt];
+  }
+
+  /// Calculate a conservative delivery-ACK timeout when firmware doesn't
+  /// provide one or returns an invalid value.
+  int calculateAckTimeoutMs({
+    required String text,
+    required Contact? contact,
+    int? suggestedTimeoutMs,
+  }) {
+    if (suggestedTimeoutMs != null && suggestedTimeoutMs > 0) {
+      return suggestedTimeoutMs;
+    }
+
+    final payloadBytes = utf8.encode(text).length;
+    final airtimeMs = _estimateLoRaAirtimeMs(payloadBytes);
+    final hopCount = contact?.routeHasPath == true
+        ? contact!.routeHopCount
+        : -1;
+
+    if (hopCount < 0) {
+      return ((airtimeMs * 10) + 4000).clamp(10000, 30000);
+    }
+
+    return ((airtimeMs * (hopCount + 1) * 2) + 1500).clamp(4000, 20000);
   }
 
-  /// Check if a message is eligible for retry
-  ///
-  /// Returns true if:
-  /// - The message has retryAttempt < 3
-  /// - The contact has a learned path (contact.hasPath == true)
-  /// - The message hasn't used flood fallback yet
-  ///
-  /// Messages to contacts without paths should NOT retry (flood mode already broadcasts)
   bool canRetry(Message message, Contact contact) {
-    // Never retry if already tried flood mode
-    if (message.usedFloodFallback) {
-      return false;
-    }
-
-    // Never retry beyond 3 attempts
-    if (message.retryAttempt >= 3) {
-      return false;
-    }
-
-    // Only retry if contact has a learned path
-    // If no path, the device uses flood mode automatically - retrying won't help
-    return contact.hasPath;
-  }
-
-  /// Check if should fall back to flood mode
-  ///
-  /// Returns true if:
-  /// - Message has exhausted all 3 retry attempts with direct mode
-  /// - Contact HAS a learned path (so direct mode was used)
-  /// - Hasn't already used flood fallback
-  ///
-  /// IMPORTANT: Only contacts WITH paths need flood fallback.
-  /// Contacts without paths already use flood mode automatically.
-  bool shouldUseFloodFallback(Message message, Contact contact) {
-    return message.retryAttempt >= 3 &&
-           contact.hasPath &&  // ✅ FIXED: Flood fallback for failed direct paths
-           !message.usedFloodFallback;
+    return message.retryAttempt < maxRetryAttempts;
   }
 
   /// Track a retry attempt for a message
@@ -87,6 +82,7 @@ class MessageRetryManager {
   void clearAll() {
     _retryAttempts.clear();
     _lastRetryTimes.clear();
+    _pathFailureStreaks.clear();
   }
 
   /// Get current retry attempt for a message (for debugging)
@@ -98,4 +94,50 @@ class MessageRetryManager {
   DateTime? getLastRetryTime(String messageId) {
     return _lastRetryTimes[messageId];
   }
+
+  /// Record a successful delivery for a contact and clear any accumulated
+  /// route failure streak for future sends.
+  void recordDeliverySuccess(Contact contact) {
+    _pathFailureStreaks.remove(contact.publicKeyHex);
+  }
+
+  /// Record a permanent route failure for a contact.
+  ///
+  /// Returns the updated failure streak so callers can decide when to reset
+  /// the learned path on the radio and in local state.
+  int recordPathFailure(Contact contact) {
+    final contactKey = contact.publicKeyHex;
+    final next = (_pathFailureStreaks[contactKey] ?? 0) + 1;
+    _pathFailureStreaks[contactKey] = next;
+    return next;
+  }
+
+  int? getPathFailureStreak(Contact contact) {
+    return _pathFailureStreaks[contact.publicKeyHex];
+  }
+
+  int _estimateLoRaAirtimeMs(int payloadLenBytes) {
+    final sf = _defaultLoRaSf;
+    final bw = _defaultLoRaBwHz.toDouble();
+    final cr = (_defaultLoRaCr - 4).clamp(1, 4);
+    final ih = _defaultLoRaExplicitHeader == 1 ? 0 : 1;
+    final de = (sf >= 11 && _defaultLoRaBwHz <= 125000) ? 1 : 0;
+
+    final symbolMs = ((1 << sf) / bw) * 1000.0;
+    final preambleMs = (_defaultLoRaPreambleSymbols + 4.25) * symbolMs;
+
+    final num =
+        (8 * payloadLenBytes) -
+        (4 * sf) +
+        28 +
+        (16 * _defaultLoRaCrcEnabled) -
+        (20 * ih);
+    final den = 4 * (sf - (2 * de));
+    final payloadSymCoeff = den <= 0 ? 0 : (num / den).ceil();
+    final payloadSymbols =
+        8 + (payloadSymCoeff < 0 ? 0 : payloadSymCoeff) * (cr + 4);
+    final payloadMs = payloadSymbols * symbolMs;
+
+    return (preambleMs + payloadMs).ceil();
+  }
 }

lib/providers/helpers/ping_tracker.dart

@@ -46,8 +46,8 @@ class PingTracker {
   /// Mark a ping as successful (response received)
   /// Should be called when telemetry response arrives
   void markPingSuccessful(Uint8List publicKey) {
-    final String keyHex = _publicKeyToHex(publicKey);
-    final request = _pendingPings.remove(keyHex);
+    final requestKey = _findMatchingPendingPingKey(publicKey);
+    final request = requestKey != null ? _pendingPings.remove(requestKey) : null;
 
     if (request != null) {
       request.cancel();
@@ -81,6 +81,23 @@ class PingTracker {
   String _publicKeyToHex(Uint8List publicKey) {
     return publicKey.map((b) => b.toRadixString(16).padLeft(2, '0')).join('');
   }
+
+  String? _findMatchingPendingPingKey(Uint8List responseKey) {
+    final responseHex = _publicKeyToHex(responseKey);
+
+    if (_pendingPings.containsKey(responseHex)) {
+      return responseHex;
+    }
+
+    for (final entry in _pendingPings.entries) {
+      final pendingHex = entry.key;
+      if (pendingHex.startsWith(responseHex) || responseHex.startsWith(pendingHex)) {
+        return pendingHex;
+      }
+    }
+
+    return null;
+  }
 }
 
 /// Internal class to track a single ping request

lib/providers/helpers/raw_session_retransmit.dart

@@ -0,0 +1,81 @@
+import 'package:flutter/foundation.dart';
+
+import '../../models/contact.dart';
+
+typedef RawPacketSender =
+    Future<void> Function({
+      required Uint8List contactPath,
+      required int contactPathLen,
+      required Uint8List payload,
+    });
+
+Future<bool> serveCachedSessionFragments<T>({
+  required String providerLabel,
+  required String sessionId,
+  required Contact requester,
+  required List<T> fragments,
+  required int maxDirectPayloadHops,
+  required int Function(T fragment) indexOf,
+  required Uint8List Function(T fragment) encodeBinary,
+  required RawPacketSender? sendRawPacket,
+  Set<int>? requestedIndices,
+}) async {
+  if (fragments.isEmpty) {
+    debugPrint('⚠️ [$providerLabel] No cached fragments for $sessionId');
+    return false;
+  }
+  if (sendRawPacket == null) {
+    debugPrint('⚠️ [$providerLabel] sendRawPacketCallback not set');
+    return false;
+  }
+  if (!requester.routeHasPath) {
+    debugPrint('⚠️ [$providerLabel] ${requester.advName} has no direct path');
+    return false;
+  }
+  if (requester.routeHopCount > maxDirectPayloadHops) {
+    debugPrint(
+      '⚠️ [$providerLabel] ${requester.advName} is too far: ${requester.routeHopCount} hops (max $maxDirectPayloadHops)',
+    );
+    return false;
+  }
+  if (requester.outPath.isEmpty) {
+    debugPrint(
+      '⚠️ [$providerLabel] ${requester.advName} has empty outPath payload',
+    );
+    return false;
+  }
+
+  var servedCount = 0;
+  for (final fragment in fragments) {
+    final index = indexOf(fragment);
+    if (index < 0) {
+      debugPrint('⚠️ [$providerLabel] Invalid fragment index $index');
+      continue;
+    }
+    if (requestedIndices != null && !requestedIndices.contains(index)) {
+      continue;
+    }
+    try {
+      await sendRawPacket(
+        contactPath: requester.outPath,
+        contactPathLen: requester.routeEncodedPathLen,
+        payload: encodeBinary(fragment),
+      );
+      servedCount++;
+    } catch (e, st) {
+      debugPrint(
+        '❌ [$providerLabel] Serve error for $sessionId#$index: $e\n$st',
+      );
+      return false;
+    }
+  }
+
+  if (servedCount == 0) {
+    debugPrint(
+      '⚠️ [$providerLabel] No fragments matched request for $sessionId',
+    );
+    return false;
+  }
+  debugPrint('✅ [$providerLabel] Served $servedCount fragments for $sessionId');
+  return true;
+}

lib/providers/helpers/session_metadata_restore.dart

@@ -0,0 +1,57 @@
+import '../../models/message.dart';
+import '../../utils/image_message_parser.dart';
+import '../../utils/voice_message_parser.dart';
+
+class RestoredSessionMetadata {
+  final Map<String, String> voiceSenderKeyBySession;
+  final Map<String, String> imageSenderKeyBySession;
+  final Map<String, ImageEnvelope> imageEnvelopeBySession;
+
+  const RestoredSessionMetadata({
+    required this.voiceSenderKeyBySession,
+    required this.imageSenderKeyBySession,
+    required this.imageEnvelopeBySession,
+  });
+}
+
+RestoredSessionMetadata restoreSessionMetadataFromMessages(
+  Iterable<Message> messages,
+) {
+  final voiceSenderKeyBySession = <String, String>{};
+  final imageSenderKeyBySession = <String, String>{};
+  final imageEnvelopeBySession = <String, ImageEnvelope>{};
+
+  for (final message in messages) {
+    final text = message.text;
+    final voiceEnvelope = VoiceEnvelope.tryParseText(text);
+    if (voiceEnvelope != null) {
+      final senderPrefix = message.senderPublicKeyPrefix;
+      if (senderPrefix != null && senderPrefix.length >= 6) {
+        voiceSenderKeyBySession[voiceEnvelope.sessionId] = senderPrefix
+            .sublist(0, 6)
+            .map((b) => b.toRadixString(16).padLeft(2, '0'))
+            .join()
+            .toLowerCase();
+      }
+    }
+
+    final imageEnvelope = ImageEnvelope.tryParse(text);
+    if (imageEnvelope != null) {
+      imageEnvelopeBySession[imageEnvelope.sessionId] = imageEnvelope;
+      final senderPrefix = message.senderPublicKeyPrefix;
+      if (senderPrefix != null && senderPrefix.length >= 6) {
+        imageSenderKeyBySession[imageEnvelope.sessionId] = senderPrefix
+            .sublist(0, 6)
+            .map((b) => b.toRadixString(16).padLeft(2, '0'))
+            .join()
+            .toLowerCase();
+      }
+    }
+  }
+
+  return RestoredSessionMetadata(
+    voiceSenderKeyBySession: voiceSenderKeyBySession,
+    imageSenderKeyBySession: imageSenderKeyBySession,
+    imageEnvelopeBySession: imageEnvelopeBySession,
+  );
+}

lib/providers/image_provider.dart

@@ -3,6 +3,7 @@ import 'dart:convert';
 import 'package:flutter/foundation.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import '../models/contact.dart';
+import 'helpers/raw_session_retransmit.dart';
 import '../utils/image_message_parser.dart';
 
 /// Reassembly state for one incoming image session.
@@ -13,6 +14,8 @@ class ImageSession {
   final int width;
   final int height;
   final List<ImagePacket?> fragments; // indexed by fragment.index
+  DateTime? firstFragmentAt;
+  DateTime? lastFragmentAt;
 
   ImageSession({
     required this.sessionId,
@@ -25,6 +28,21 @@ class ImageSession {
   int get receivedCount => fragments.where((f) => f != null).length;
   bool get isComplete => receivedCount == total;
 
+  Duration? estimateRemaining() {
+    if (isComplete) return Duration.zero;
+    if (firstFragmentAt == null || lastFragmentAt == null) return null;
+    if (receivedCount < 2) return null;
+
+    final elapsedMs = lastFragmentAt!
+        .difference(firstFragmentAt!)
+        .inMilliseconds;
+    if (elapsedMs <= 0) return null;
+    final avgMsPerFragment = elapsedMs / (receivedCount - 1);
+    final remaining = total - receivedCount;
+    if (remaining <= 0) return Duration.zero;
+    return Duration(milliseconds: (avgMsPerFragment * remaining).round());
+  }
+
   /// Reassemble the complete image bytes, or null if any fragment is missing.
   Uint8List? get imageBytes => reassembleImage(fragments);
 }
@@ -40,6 +58,7 @@ class ImageProvider with ChangeNotifier {
 
   /// Incoming sessions keyed by sessionId.
   final Map<String, ImageSession> _sessions = {};
+  final Set<String> _ignoredIncomingSessions = {};
 
   /// Outgoing sessions cached for deferred serving.
   final Map<String, _OutgoingSession> _outgoing = {};
@@ -62,6 +81,10 @@ class ImageProvider with ChangeNotifier {
   bool isComplete(String sessionId) =>
       _sessions[sessionId]?.isComplete ?? false;
   bool hasOutgoing(String sessionId) => _outgoing.containsKey(sessionId);
+  Duration? estimateRemainingTransferTime(String sessionId) =>
+      _sessions[sessionId]?.estimateRemaining();
+  bool isReceiveCanceled(String sessionId) =>
+      _ignoredIncomingSessions.contains(sessionId);
 
   List<int> missingFragmentIndices(String sessionId) {
     final session = _sessions[sessionId];
@@ -73,28 +96,61 @@ class ImageProvider with ChangeNotifier {
     return missing;
   }
 
+  List<int> availableFragmentIndices(String sessionId) {
+    final outgoing = _outgoing[sessionId];
+    if (outgoing != null) {
+      return outgoing.fragments.map((fragment) => fragment.index).toList()
+        ..sort();
+    }
+
+    final session = _sessions[sessionId];
+    if (session == null) return const [];
+    final indices = <int>[];
+    for (var i = 0; i < session.fragments.length; i++) {
+      if (session.fragments[i] != null) {
+        indices.add(i);
+      }
+    }
+    return indices;
+  }
+
   // ── Incoming fragment reception ──────────────────────────────────────────
 
-  /// Add a received [fragment].  Creates the session on first fragment using
-  /// metadata from the fragment itself (requires envelope to have been
-  /// announced first; if not, defaults width/height to 0 — corrected on save).
+  /// Add a received [fragment]. New compact fragments rely on prior envelope
+  /// metadata for total/format, while legacy fragments can still self-describe.
   ///
   /// Returns true when the session just became complete.
   bool addFragment(ImagePacket fragment, {int width = 0, int height = 0}) {
-    _sessions.putIfAbsent(
-      fragment.sessionId,
-      () => ImageSession(
+    if (_ignoredIncomingSessions.contains(fragment.sessionId)) {
+      debugPrint(
+        '⏹️ [ImageProvider] Ignoring canceled incoming session ${fragment.sessionId}',
+      );
+      return false;
+    }
+    _sessions.putIfAbsent(fragment.sessionId, () {
+      if (fragment.total < 1) {
+        throw StateError(
+          'Image envelope missing for compact fragment ${fragment.sessionId}',
+        );
+      }
+      return ImageSession(
         sessionId: fragment.sessionId,
         format: fragment.format,
         total: fragment.total,
         width: width,
         height: height,
-      ),
-    );
+      );
+    });
 
     final session = _sessions[fragment.sessionId]!;
     if (fragment.index < session.total) {
+      final wasMissing = session.fragments[fragment.index] == null;
       session.fragments[fragment.index] = fragment;
+      if (wasMissing) {
+        final now = DateTime.now();
+        session.firstFragmentAt ??= now;
+        session.lastFragmentAt = now;
+      }
     }
 
     final justComplete = session.isComplete;
@@ -103,22 +159,27 @@ class ImageProvider with ChangeNotifier {
     return justComplete;
   }
 
+  void cancelIncomingSession(String sessionId) {
+    _ignoredIncomingSessions.add(sessionId);
+    _sessions.remove(sessionId);
+    unawaited(_persist());
+    notifyListeners();
+  }
+
+  void resumeIncomingSession(String sessionId) {
+    if (_ignoredIncomingSessions.remove(sessionId)) {
+      notifyListeners();
+    }
+  }
+
   /// Register envelope metadata for a session (called when IE1 is received
   /// before any binary fragments arrive).
   void registerEnvelope(ImageEnvelope envelope) {
-    _sessions.putIfAbsent(
-      envelope.sessionId,
-      () => ImageSession(
-        sessionId: envelope.sessionId,
-        format: envelope.format,
-        total: envelope.total,
-        width: envelope.width,
-        height: envelope.height,
-      ),
-    );
-    // Update dimensions if we created the session from a fragment (w/h = 0).
-    final session = _sessions[envelope.sessionId]!;
-    if (session.width == 0 || session.height == 0) {
+    if (_ignoredIncomingSessions.contains(envelope.sessionId)) {
+      return;
+    }
+    final existing = _sessions[envelope.sessionId];
+    if (existing == null) {
       _sessions[envelope.sessionId] = ImageSession(
         sessionId: envelope.sessionId,
         format: envelope.format,
@@ -126,12 +187,38 @@ class ImageProvider with ChangeNotifier {
         width: envelope.width,
         height: envelope.height,
       );
-      // Copy existing fragments into the new session.
-      final old = _sessions[envelope.sessionId]!;
-      for (var i = 0; i < session.fragments.length && i < old.total; i++) {
-        old.fragments[i] = session.fragments[i];
+      unawaited(_persist());
+      notifyListeners();
+      return;
+    }
+
+    final needsMerge =
+        existing.width == 0 ||
+        existing.height == 0 ||
+        existing.total != envelope.total ||
+        existing.format != envelope.format;
+    if (!needsMerge) {
+      notifyListeners();
+      return;
+    }
+
+    final merged = ImageSession(
+      sessionId: envelope.sessionId,
+      format: envelope.format,
+      total: envelope.total,
+      width: envelope.width,
+      height: envelope.height,
+    );
+    merged.firstFragmentAt = existing.firstFragmentAt;
+    merged.lastFragmentAt = existing.lastFragmentAt;
+    for (final fragment in existing.fragments) {
+      if (fragment == null) continue;
+      if (fragment.index < merged.total) {
+        merged.fragments[fragment.index] = fragment;
       }
     }
+    _sessions[envelope.sessionId] = merged;
+    unawaited(_persist());
     notifyListeners();
   }
 
@@ -178,46 +265,28 @@ class ImageProvider with ChangeNotifier {
     required Contact requester,
     Set<int>? requestedIndices,
   }) async {
-    final cached = _outgoing[sessionId];
-    if (cached == null) {
-      debugPrint('⚠️ [ImageProvider] No cached session for $sessionId');
-      return false;
-    }
-    if (sendRawPacketCallback == null) {
-      debugPrint('⚠️ [ImageProvider] sendRawPacketCallback not set');
-      return false;
-    }
-    if (requester.outPathLen < 0) {
-      debugPrint('⚠️ [ImageProvider] ${requester.advName} has no direct path');
-      return false;
-    }
-    if (requester.outPathLen > maxDirectPayloadHops) {
+    final outgoing = _outgoing[sessionId];
+    final fragments = outgoing != null
+        ? List<ImagePacket>.from(outgoing.fragments)
+        : _sessions[sessionId]?.fragments.whereType<ImagePacket>().toList() ??
+              const <ImagePacket>[];
+    if (fragments.isEmpty) {
       debugPrint(
-        '⚠️ [ImageProvider] ${requester.advName} is too far: ${requester.outPathLen} hops (max $maxDirectPayloadHops)',
+        '⚠️ [ImageProvider] No cached or received session for $sessionId',
       );
       return false;
     }
-
-    for (final fragment in cached.fragments) {
-      if (requestedIndices != null &&
-          !requestedIndices.contains(fragment.index)) {
-        continue;
-      }
-      try {
-        await sendRawPacketCallback!(
-          contactPath: requester.outPath,
-          contactPathLen: requester.outPathLen,
-          payload: fragment.encodeBinary(),
-        );
-      } catch (e, st) {
-        debugPrint('❌ [ImageProvider] Serve error for $sessionId: $e\n$st');
-        return false;
-      }
-    }
-    debugPrint(
-      '📷 [ImageProvider] Served ${cached.fragments.length} fragments of $sessionId',
+    return serveCachedSessionFragments<ImagePacket>(
+      providerLabel: 'ImageProvider',
+      sessionId: sessionId,
+      requester: requester,
+      fragments: fragments,
+      maxDirectPayloadHops: maxDirectPayloadHops,
+      indexOf: (fragment) => fragment.index,
+      encodeBinary: (fragment) => fragment.encodeBinary(),
+      sendRawPacket: sendRawPacketCallback,
+      requestedIndices: requestedIndices,
     );
-    return true;
   }
 
   // ── Persistence ──────────────────────────────────────────────────────────
@@ -225,6 +294,7 @@ class ImageProvider with ChangeNotifier {
   Future<void> clearAll() async {
     _sessions.clear();
     _outgoing.clear();
+    _ignoredIncomingSessions.clear();
     notifyListeners();
     try {
       final prefs = await SharedPreferences.getInstance();

lib/providers/sensors_provider.dart

@@ -0,0 +1,300 @@
+import 'dart:async';
+import 'dart:convert';
+
+import 'package:flutter/foundation.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import '../models/contact.dart';
+import 'connection_provider.dart';
+import 'contacts_provider.dart';
+
+enum SensorRefreshState { idle, refreshing, success, timeout, unavailable }
+
+class SensorsProvider with ChangeNotifier {
+  static const Duration _successStateRetention = Duration(minutes: 1);
+  static const String _watchedSensorsKey = 'watched_sensor_keys';
+  static const String _visibleSensorMetricsKey = 'visible_sensor_metrics';
+  static const String _fieldSpanKey = 'sensor_field_spans';
+  static const Set<String> _defaultVisibleFields = <String>{
+    'voltage',
+    'battery',
+    'temperature',
+    'humidity',
+    'pressure',
+    'gps',
+  };
+
+  final List<String> _watchedSensorKeys = <String>[];
+  final Map<String, SensorRefreshState> _refreshStates =
+      <String, SensorRefreshState>{};
+  final Map<String, DateTime> _refreshStateUpdatedAt = <String, DateTime>{};
+  final Map<String, Set<String>> _visibleFieldsBySensor =
+      <String, Set<String>>{};
+  final Map<String, Map<String, int>> _fieldSpansBySensor =
+      <String, Map<String, int>>{};
+  bool _isLoaded = false;
+  bool _isRefreshingAll = false;
+
+  SensorsProvider() {
+    unawaited(_loadWatchedSensors());
+  }
+
+  List<String> get watchedSensorKeys => List.unmodifiable(_watchedSensorKeys);
+  bool get isLoaded => _isLoaded;
+  bool get isRefreshingAll => _isRefreshingAll;
+
+  SensorRefreshState stateFor(String publicKeyHex) =>
+      _refreshStates[publicKeyHex] ?? SensorRefreshState.idle;
+
+  Future<void> _loadWatchedSensors() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final stored = prefs.getStringList(_watchedSensorsKey) ?? <String>[];
+      final storedMetricsJson = prefs.getString(_visibleSensorMetricsKey);
+      final storedSpansJson = prefs.getString(_fieldSpanKey);
+      _watchedSensorKeys
+        ..clear()
+        ..addAll(stored);
+      _visibleFieldsBySensor.clear();
+      _fieldSpansBySensor.clear();
+      if (storedMetricsJson != null && storedMetricsJson.isNotEmpty) {
+        final decoded = jsonDecode(storedMetricsJson) as Map<String, dynamic>;
+        for (final entry in decoded.entries) {
+          _visibleFieldsBySensor[entry.key] = (entry.value as List<dynamic>)
+              .cast<String>()
+              .toSet();
+        }
+      }
+      if (storedSpansJson != null && storedSpansJson.isNotEmpty) {
+        final decoded = jsonDecode(storedSpansJson) as Map<String, dynamic>;
+        for (final entry in decoded.entries) {
+          _fieldSpansBySensor[entry.key] = (entry.value as Map<String, dynamic>)
+              .map((key, value) => MapEntry(key, value as int));
+        }
+      }
+      for (final key in _watchedSensorKeys) {
+        _visibleFieldsBySensor.putIfAbsent(
+          key,
+          () => Set<String>.from(_defaultVisibleFields),
+        );
+        _fieldSpansBySensor.putIfAbsent(key, () => <String, int>{});
+      }
+    } catch (e) {
+      debugPrint('Error loading watched sensors: $e');
+    } finally {
+      _isLoaded = true;
+      notifyListeners();
+    }
+  }
+
+  Future<void> _persistWatchedSensors() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      await prefs.setStringList(_watchedSensorsKey, _watchedSensorKeys);
+    } catch (e) {
+      debugPrint('Error saving watched sensors: $e');
+    }
+  }
+
+  Future<void> _persistVisibleMetrics() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final encoded = <String, List<String>>{};
+      for (final entry in _visibleFieldsBySensor.entries) {
+        encoded[entry.key] = entry.value.toList();
+      }
+      await prefs.setString(_visibleSensorMetricsKey, jsonEncode(encoded));
+    } catch (e) {
+      debugPrint('Error saving visible sensor metrics: $e');
+    }
+  }
+
+  Future<void> _persistFieldSpans() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      await prefs.setString(_fieldSpanKey, jsonEncode(_fieldSpansBySensor));
+    } catch (e) {
+      debugPrint('Error saving sensor field spans: $e');
+    }
+  }
+
+  Set<String> visibleFieldsFor(String publicKeyHex) => Set<String>.unmodifiable(
+    _visibleFieldsBySensor[publicKeyHex] ?? _defaultVisibleFields,
+  );
+
+  bool showsField(String publicKeyHex, String fieldKey) =>
+      visibleFieldsFor(publicKeyHex).contains(fieldKey);
+
+  int fieldSpanFor(String publicKeyHex, String fieldKey) {
+    final sensorSpans = _fieldSpansBySensor[publicKeyHex];
+    final span = sensorSpans?[fieldKey] ?? 1;
+    return span == 2 ? 2 : 1;
+  }
+
+  Future<void> toggleMetric(
+    String publicKeyHex,
+    String fieldKey,
+    bool visible,
+  ) async {
+    final visibleFields = _visibleFieldsBySensor.putIfAbsent(
+      publicKeyHex,
+      () => Set<String>.from(_defaultVisibleFields),
+    );
+    if (visible) {
+      visibleFields.add(fieldKey);
+    } else {
+      if (visibleFields.length == 1 && visibleFields.contains(fieldKey)) {
+        return;
+      }
+      visibleFields.remove(fieldKey);
+    }
+    await _persistVisibleMetrics();
+    notifyListeners();
+  }
+
+  Future<void> setFieldSpan(
+    String publicKeyHex,
+    String fieldKey,
+    int span,
+  ) async {
+    final sensorSpans = _fieldSpansBySensor.putIfAbsent(
+      publicKeyHex,
+      () => <String, int>{},
+    );
+    sensorSpans[fieldKey] = span == 2 ? 2 : 1;
+    await _persistFieldSpans();
+    notifyListeners();
+  }
+
+  bool isWatched(String publicKeyHex) =>
+      _watchedSensorKeys.contains(publicKeyHex);
+
+  Future<void> addSensor(Contact contact) async {
+    if (!contact.isChat && !contact.isRepeater) {
+      return;
+    }
+    if (_watchedSensorKeys.contains(contact.publicKeyHex)) {
+      return;
+    }
+
+    _watchedSensorKeys.add(contact.publicKeyHex);
+    await _persistWatchedSensors();
+    _visibleFieldsBySensor[contact.publicKeyHex] = Set<String>.from(
+      _defaultVisibleFields,
+    );
+    _fieldSpansBySensor[contact.publicKeyHex] = <String, int>{'gps': 2};
+    await _persistVisibleMetrics();
+    await _persistFieldSpans();
+    notifyListeners();
+  }
+
+  Future<void> removeSensor(String publicKeyHex) async {
+    _watchedSensorKeys.remove(publicKeyHex);
+    _refreshStates.remove(publicKeyHex);
+    _refreshStateUpdatedAt.remove(publicKeyHex);
+    _visibleFieldsBySensor.remove(publicKeyHex);
+    _fieldSpansBySensor.remove(publicKeyHex);
+    await _persistWatchedSensors();
+    await _persistVisibleMetrics();
+    await _persistFieldSpans();
+    notifyListeners();
+  }
+
+  List<Contact> availableCandidates(ContactsProvider contactsProvider) {
+    final candidates = <Contact>[
+      ...contactsProvider.chatContacts,
+      ...contactsProvider.repeaters,
+    ];
+    candidates.removeWhere((contact) => isWatched(contact.publicKeyHex));
+    candidates.sort((a, b) => b.lastSeenTime.compareTo(a.lastSeenTime));
+    return candidates;
+  }
+
+  Future<void> refreshAll({
+    required ContactsProvider contactsProvider,
+    required ConnectionProvider connectionProvider,
+  }) async {
+    if (_isRefreshingAll || _watchedSensorKeys.isEmpty) {
+      return;
+    }
+
+    _isRefreshingAll = true;
+    notifyListeners();
+
+    try {
+      for (final key in _watchedSensorKeys) {
+        await refreshSensor(
+          publicKeyHex: key,
+          contactsProvider: contactsProvider,
+          connectionProvider: connectionProvider,
+        );
+      }
+    } finally {
+      _isRefreshingAll = false;
+      notifyListeners();
+    }
+  }
+
+  Future<void> refreshSensor({
+    required String publicKeyHex,
+    required ContactsProvider contactsProvider,
+    required ConnectionProvider connectionProvider,
+  }) async {
+    Contact? contact;
+    for (final entry in contactsProvider.contacts) {
+      if (entry.publicKeyHex == publicKeyHex) {
+        contact = entry;
+        break;
+      }
+    }
+
+    if (contact == null) {
+      _setRefreshState(publicKeyHex, SensorRefreshState.unavailable);
+      return;
+    }
+
+    _setRefreshState(publicKeyHex, SensorRefreshState.refreshing);
+
+    final result = await connectionProvider.smartPing(
+      contactPublicKey: contact.publicKey,
+      hasPath: contact.hasPath,
+    );
+
+    _setRefreshState(
+      publicKeyHex,
+      result.success ? SensorRefreshState.success : SensorRefreshState.timeout,
+    );
+  }
+
+  void clearExpiredRefreshStates({DateTime? now}) {
+    final cutoff = (now ?? DateTime.now()).subtract(_successStateRetention);
+    final keysToClear = <String>[];
+
+    for (final entry in _refreshStates.entries) {
+      if (entry.value != SensorRefreshState.success) {
+        continue;
+      }
+
+      final updatedAt = _refreshStateUpdatedAt[entry.key];
+      if (updatedAt == null || !updatedAt.isAfter(cutoff)) {
+        keysToClear.add(entry.key);
+      }
+    }
+
+    if (keysToClear.isEmpty) {
+      return;
+    }
+
+    for (final key in keysToClear) {
+      _refreshStates.remove(key);
+      _refreshStateUpdatedAt.remove(key);
+    }
+    notifyListeners();
+  }
+
+  void _setRefreshState(String publicKeyHex, SensorRefreshState state) {
+    _refreshStates[publicKeyHex] = state;
+    _refreshStateUpdatedAt[publicKeyHex] = DateTime.now();
+    notifyListeners();
+  }
+}

lib/providers/voice_provider.dart

@@ -3,6 +3,7 @@ import 'dart:convert';
 import 'package:flutter/foundation.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import '../models/contact.dart';
+import 'helpers/raw_session_retransmit.dart';
 import '../utils/voice_message_parser.dart';
 import '../services/voice_codec_service.dart';
 import '../services/voice_player_service.dart';
@@ -13,6 +14,8 @@ class VoiceSession {
   final VoicePacketMode mode;
   final int total;
   final List<VoicePacket?> packets; // indexed by packet.index
+  DateTime? firstPacketAt;
+  DateTime? lastPacketAt;
 
   VoiceSession({
     required this.sessionId,
@@ -23,6 +26,19 @@ class VoiceSession {
   int get receivedCount => packets.where((p) => p != null).length;
   bool get isComplete => receivedCount == total;
 
+  Duration? estimateRemaining() {
+    if (isComplete) return Duration.zero;
+    if (firstPacketAt == null || lastPacketAt == null) return null;
+    if (receivedCount < 2) return null;
+
+    final elapsedMs = lastPacketAt!.difference(firstPacketAt!).inMilliseconds;
+    if (elapsedMs <= 0) return null;
+    final avgMsPerPacket = elapsedMs / (receivedCount - 1);
+    final remaining = total - receivedCount;
+    if (remaining <= 0) return Duration.zero;
+    return Duration(milliseconds: (avgMsPerPacket * remaining).round());
+  }
+
   /// Total estimated audio duration in seconds (sum of all received packets).
   double get estimatedDurationSeconds {
     var ms = 0;
@@ -43,6 +59,7 @@ class VoiceProvider with ChangeNotifier {
 
   /// Active sessions keyed by sessionId.
   final Map<String, VoiceSession> _sessions = {};
+  final Set<String> _ignoredIncomingSessions = {};
 
   /// Currently playing session ID, or null.
   String? _playingSessionId;
@@ -93,6 +110,10 @@ class VoiceProvider with ChangeNotifier {
 
   bool hasOutgoingSession(String sessionId) =>
       _outgoingSessions.containsKey(sessionId);
+  Duration? estimateRemainingTransferTime(String sessionId) =>
+      _sessions[sessionId]?.estimateRemaining();
+  bool isReceiveCanceled(String sessionId) =>
+      _ignoredIncomingSessions.contains(sessionId);
 
   List<int> missingPacketIndices(String sessionId) {
     final session = _sessions[sessionId];
@@ -104,23 +125,56 @@ class VoiceProvider with ChangeNotifier {
     return missing;
   }
 
+  List<int> availablePacketIndices(String sessionId) {
+    final outgoing = _outgoingSessions[sessionId];
+    if (outgoing != null) {
+      return outgoing.packets.map((packet) => packet.index).toList()..sort();
+    }
+
+    final session = _sessions[sessionId];
+    if (session == null) return const [];
+    final indices = <int>[];
+    for (var i = 0; i < session.packets.length; i++) {
+      if (session.packets[i] != null) {
+        indices.add(i);
+      }
+    }
+    return indices;
+  }
+
   // ── Packet reception ─────────────────────────────────────────────────────
 
   /// Add an incoming [packet] to its session.  Creates the session on first packet.
   /// Returns true if the session just became complete.
   bool addPacket(VoicePacket packet) {
-    _sessions.putIfAbsent(
-      packet.sessionId,
-      () => VoiceSession(
+    if (_ignoredIncomingSessions.contains(packet.sessionId)) {
+      debugPrint(
+        '⏹️ [VoiceProvider] Ignoring canceled incoming session ${packet.sessionId}',
+      );
+      return false;
+    }
+    _sessions.putIfAbsent(packet.sessionId, () {
+      if (packet.total < 1) {
+        throw StateError(
+          'Voice envelope missing for compact packet ${packet.sessionId}',
+        );
+      }
+      return VoiceSession(
         sessionId: packet.sessionId,
         mode: packet.mode,
         total: packet.total,
-      ),
-    );
+      );
+    });
 
     final session = _sessions[packet.sessionId]!;
     if (packet.index < session.total) {
+      final wasMissing = session.packets[packet.index] == null;
       session.packets[packet.index] = packet;
+      if (wasMissing) {
+        final now = DateTime.now();
+        session.firstPacketAt ??= now;
+        session.lastPacketAt = now;
+      }
     }
 
     final justComplete = session.isComplete;
@@ -129,6 +183,64 @@ class VoiceProvider with ChangeNotifier {
     return justComplete;
   }
 
+  void cancelIncomingSession(String sessionId) {
+    _ignoredIncomingSessions.add(sessionId);
+    _sessions.remove(sessionId);
+    if (_playingSessionId == sessionId) {
+      unawaited(_player.stop());
+      _playingSessionId = null;
+    }
+    _persistVoiceData();
+    notifyListeners();
+  }
+
+  void resumeIncomingSession(String sessionId) {
+    if (_ignoredIncomingSessions.remove(sessionId)) {
+      notifyListeners();
+    }
+  }
+
+  void registerEnvelope(VoiceEnvelope envelope) {
+    if (_ignoredIncomingSessions.contains(envelope.sessionId)) {
+      return;
+    }
+    final existing = _sessions[envelope.sessionId];
+    if (existing == null) {
+      _sessions[envelope.sessionId] = VoiceSession(
+        sessionId: envelope.sessionId,
+        mode: envelope.mode,
+        total: envelope.total,
+      );
+      _persistVoiceData();
+      notifyListeners();
+      return;
+    }
+
+    final needsMerge =
+        existing.total != envelope.total || existing.mode != envelope.mode;
+    if (!needsMerge) {
+      notifyListeners();
+      return;
+    }
+
+    final merged = VoiceSession(
+      sessionId: envelope.sessionId,
+      mode: envelope.mode,
+      total: envelope.total,
+    );
+    merged.firstPacketAt = existing.firstPacketAt;
+    merged.lastPacketAt = existing.lastPacketAt;
+    for (final packet in existing.packets) {
+      if (packet == null) continue;
+      if (packet.index < merged.total) {
+        merged.packets[packet.index] = packet;
+      }
+    }
+    _sessions[envelope.sessionId] = merged;
+    _persistVoiceData();
+    notifyListeners();
+  }
+
   /// Cache encoded packets for deferred voice serving.
   void cacheOutgoingSession(String sessionId, List<VoicePacket> packets) {
     if (packets.isEmpty) return;
@@ -145,49 +257,28 @@ class VoiceProvider with ChangeNotifier {
     required Contact requester,
     Set<int>? requestedIndices,
   }) async {
-    final cached = _outgoingSessions[sessionId];
-    if (cached == null) {
+    final outgoing = _outgoingSessions[sessionId];
+    final packets = outgoing != null
+        ? List<VoicePacket>.from(outgoing.packets)
+        : _sessions[sessionId]?.packets.whereType<VoicePacket>().toList() ??
+              const <VoicePacket>[];
+    if (packets.isEmpty) {
       debugPrint(
-        '⚠️ [VoiceProvider] No cached outgoing session for $sessionId',
+        '⚠️ [VoiceProvider] No cached or received session for $sessionId',
       );
       return false;
     }
-    if (sendRawPacketCallback == null) {
-      debugPrint('⚠️ [VoiceProvider] sendRawPacketCallback is not set');
-      return false;
-    }
-    if (requester.outPathLen < 0) {
-      debugPrint(
-        '⚠️ [VoiceProvider] Requester ${requester.advName} has no direct path',
-      );
-      return false;
-    }
-    if (requester.outPathLen > maxDirectPayloadHops) {
-      debugPrint(
-        '⚠️ [VoiceProvider] Requester ${requester.advName} is too far: ${requester.outPathLen} hops (max $maxDirectPayloadHops)',
-      );
-      return false;
-    }
-
-    for (final packet in cached.packets) {
-      if (requestedIndices != null &&
-          !requestedIndices.contains(packet.index)) {
-        continue;
-      }
-      try {
-        await sendRawPacketCallback!(
-          contactPath: requester.outPath,
-          contactPathLen: requester.outPathLen,
-          payload: packet.encodeBinary(),
-        );
-      } catch (e, st) {
-        debugPrint(
-          '❌ [VoiceProvider] Failed serving packet for $sessionId: $e\n$st',
-        );
-        return false;
-      }
-    }
-    return true;
+    return serveCachedSessionFragments<VoicePacket>(
+      providerLabel: 'VoiceProvider',
+      sessionId: sessionId,
+      requester: requester,
+      fragments: packets,
+      maxDirectPayloadHops: maxDirectPayloadHops,
+      indexOf: (packet) => packet.index,
+      encodeBinary: (packet) => packet.encodeBinary(),
+      sendRawPacket: sendRawPacketCallback,
+      requestedIndices: requestedIndices,
+    );
   }
 
   // ── Playback ─────────────────────────────────────────────────────────────
@@ -231,6 +322,7 @@ class VoiceProvider with ChangeNotifier {
   Future<void> clearStoredVoiceData() async {
     _sessions.clear();
     _outgoingSessions.clear();
+    _ignoredIncomingSessions.clear();
     _playingSessionId = null;
     notifyListeners();
     try {

lib/screens/contacts_tab.dart

@@ -3,16 +3,27 @@ import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:geolocator/geolocator.dart';
 import '../l10n/app_localizations.dart';
+import '../models/contact.dart';
 import '../providers/contacts_provider.dart';
 import '../providers/app_provider.dart';
 import '../providers/connection_provider.dart';
+import '../providers/messages_provider.dart';
+import '../services/message_destination_preferences.dart';
+import '../utils/contact_grouping.dart';
+import '../utils/avatar_label_helper.dart';
+import '../widgets/common/contact_avatar.dart';
 import '../widgets/contacts/contact_tile.dart';
 import '../widgets/contacts/add_channel_dialog.dart';
 
 class ContactsTab extends StatefulWidget {
   final VoidCallback? onNavigateToMap;
+  final VoidCallback? onNavigateToMessages;
 
-  const ContactsTab({super.key, this.onNavigateToMap});
+  const ContactsTab({
+    super.key,
+    this.onNavigateToMap,
+    this.onNavigateToMessages,
+  });
 
   @override
   State<ContactsTab> createState() => _ContactsTabState();
@@ -21,6 +32,11 @@ class ContactsTab extends StatefulWidget {
 class _ContactsTabState extends State<ContactsTab> {
   Position? _currentPosition;
   final Set<String> _resolvingAdvertKeys = <String>{};
+  final Map<ContactSection, ContactSortMode> _sortModes = {
+    ContactSection.teamMembers: ContactSortMode.lastSeen,
+    ContactSection.repeaters: ContactSortMode.lastSeen,
+    ContactSection.rooms: ContactSortMode.lastSeen,
+  };
 
   @override
   void initState() {
@@ -119,6 +135,54 @@ class _ContactsTabState extends State<ContactsTab> {
     return l10n.daysAgo(diff.inDays);
   }
 
+  List<Contact> _sortContacts(List<Contact> contacts, ContactSection section) {
+    final sorted = List<Contact>.from(contacts);
+    if (section == ContactSection.channels) {
+      sorted.sort(
+        (a, b) =>
+            a.displayName.toLowerCase().compareTo(b.displayName.toLowerCase()),
+      );
+      return sorted;
+    }
+
+    final sortMode = _sortModes[section] ?? ContactSortMode.lastSeen;
+
+    sorted.sort((a, b) {
+      if (sortMode == ContactSortMode.distance) {
+        final distanceA = _distanceFromCurrentPosition(a);
+        final distanceB = _distanceFromCurrentPosition(b);
+
+        if (distanceA != null && distanceB != null) {
+          final distanceCompare = distanceA.compareTo(distanceB);
+          if (distanceCompare != 0) return distanceCompare;
+        } else if (distanceA != null) {
+          return -1;
+        } else if (distanceB != null) {
+          return 1;
+        }
+      }
+
+      return b.lastSeenTime.compareTo(a.lastSeenTime);
+    });
+
+    return sorted;
+  }
+
+  double? _distanceFromCurrentPosition(Contact contact) {
+    final currentPosition = _currentPosition;
+    final contactLocation = contact.displayLocation;
+    if (currentPosition == null || contactLocation == null) {
+      return null;
+    }
+
+    return _calculateDistanceInMeters(
+      currentPosition.latitude,
+      currentPosition.longitude,
+      contactLocation.latitude,
+      contactLocation.longitude,
+    );
+  }
+
   /// Show the add channel dialog
   Future<void> _showAddChannelDialog(BuildContext context) async {
     final l10n = AppLocalizations.of(context)!;
@@ -165,17 +229,31 @@ class _ContactsTabState extends State<ContactsTab> {
     return Scaffold(
       body: Consumer<ContactsProvider>(
         builder: (context, contactsProvider, child) {
-          final chatContacts = contactsProvider.chatContacts;
-          final repeaters = contactsProvider.repeaters;
-          final rooms = contactsProvider.rooms;
-          final channels = contactsProvider.channels;
+          final messagesProvider = context.watch<MessagesProvider>();
+          final chatContacts = _sortContacts(
+            contactsProvider.chatContacts,
+            ContactSection.teamMembers,
+          );
+          final repeaters = _sortContacts(
+            contactsProvider.repeaters,
+            ContactSection.repeaters,
+          );
+          final rooms = _sortContacts(
+            contactsProvider.rooms,
+            ContactSection.rooms,
+          );
+          final channels = _sortContacts(
+            contactsProvider.channels,
+            ContactSection.channels,
+          );
           final pendingAdverts = contactsProvider.pendingAdverts;
 
-          // Check if there are any displayable contacts (excluding channels)
+          // Check if there are any displayable contacts
           final hasDisplayableContacts =
               chatContacts.isNotEmpty ||
               repeaters.isNotEmpty ||
               rooms.isNotEmpty ||
+              channels.isNotEmpty ||
               pendingAdverts.isNotEmpty;
 
           if (!hasDisplayableContacts) {
@@ -236,16 +314,12 @@ class _ContactsTabState extends State<ContactsTab> {
                     title: l10n.teamMembers,
                     count: chatContacts.length,
                     icon: Icons.people,
-                  ),
-                  ...chatContacts.map(
-                    (contact) => ContactTile(
-                      contact: contact,
-                      currentPosition: _currentPosition,
-                      calculateDistance: _calculateDistanceInMeters,
-                      formatDistance: _formatDistance,
-                      onNavigateToMap: widget.onNavigateToMap,
+                    trailing: _buildSortMenu(
+                      context,
+                      ContactSection.teamMembers,
                     ),
                   ),
+                  ..._buildContactSectionItems(chatContacts),
                   const Divider(height: 32),
                 ],
 
@@ -255,16 +329,9 @@ class _ContactsTabState extends State<ContactsTab> {
                     title: l10n.repeaters,
                     count: repeaters.length,
                     icon: Icons.router,
+                    trailing: _buildSortMenu(context, ContactSection.repeaters),
                   ),
-                  ...repeaters.map(
-                    (contact) => ContactTile(
-                      contact: contact,
-                      currentPosition: _currentPosition,
-                      calculateDistance: _calculateDistanceInMeters,
-                      formatDistance: _formatDistance,
-                      onNavigateToMap: widget.onNavigateToMap,
-                    ),
-                  ),
+                  ..._buildContactSectionItems(repeaters),
                   const Divider(height: 32),
                 ],
 
@@ -274,16 +341,9 @@ class _ContactsTabState extends State<ContactsTab> {
                     title: l10n.rooms,
                     count: rooms.length,
                     icon: Icons.tag,
+                    trailing: _buildSortMenu(context, ContactSection.rooms),
                   ),
-                  ...rooms.map(
-                    (contact) => ContactTile(
-                      contact: contact,
-                      currentPosition: _currentPosition,
-                      calculateDistance: _calculateDistanceInMeters,
-                      formatDistance: _formatDistance,
-                      onNavigateToMap: widget.onNavigateToMap,
-                    ),
-                  ),
+                  ..._buildContactSectionItems(rooms),
                   const Divider(height: 32),
                 ],
 
@@ -295,12 +355,11 @@ class _ContactsTabState extends State<ContactsTab> {
                 ),
                 if (channels.isNotEmpty) ...[
                   ...channels.map(
-                    (contact) => ContactTile(
-                      contact: contact,
-                      currentPosition: _currentPosition,
-                      calculateDistance: _calculateDistanceInMeters,
-                      formatDistance: _formatDistance,
-                      onNavigateToMap: widget.onNavigateToMap,
+                    (channel) => _ChannelActivityCard(
+                      channel: channel,
+                      messagesProvider: messagesProvider,
+                      contactsProvider: contactsProvider,
+                      onNavigateToMessages: widget.onNavigateToMessages,
                     ),
                   ),
                 ],
@@ -331,8 +390,97 @@ class _ContactsTabState extends State<ContactsTab> {
       ),
     );
   }
+
+  List<Widget> _buildContactSectionItems(List<Contact> contacts) {
+    final items = ContactGrouping.buildItemsFromSorted(contacts);
+
+    return items.map((item) {
+      if (item.isGroup) {
+        return _InferredContactGroupCard(
+          label: item.group!.label,
+          contacts: item.group!.contacts,
+          currentPosition: _currentPosition,
+          calculateDistance: _calculateDistanceInMeters,
+          formatDistance: _formatDistance,
+          onNavigateToMap: widget.onNavigateToMap,
+          onNavigateToMessages: widget.onNavigateToMessages,
+        );
+      }
+
+      return ContactTile(
+        contact: item.contact!,
+        currentPosition: _currentPosition,
+        calculateDistance: _calculateDistanceInMeters,
+        formatDistance: _formatDistance,
+        onNavigateToMap: widget.onNavigateToMap,
+        onNavigateToMessages: widget.onNavigateToMessages,
+      );
+    }).toList();
+  }
+
+  Widget _buildSortMenu(BuildContext context, ContactSection section) {
+    final l10n = AppLocalizations.of(context)!;
+    final selectedMode = _sortModes[section] ?? ContactSortMode.lastSeen;
+    final colorScheme = Theme.of(context).colorScheme;
+
+    return PopupMenuButton<ContactSortMode>(
+      tooltip: 'Sort',
+      initialValue: selectedMode,
+      onSelected: (sortMode) {
+        setState(() {
+          _sortModes[section] = sortMode;
+        });
+      },
+      itemBuilder: (context) => [
+        PopupMenuItem<ContactSortMode>(
+          value: ContactSortMode.lastSeen,
+          child: Row(
+            children: [
+              Icon(
+                Icons.schedule,
+                size: 18,
+                color: selectedMode == ContactSortMode.lastSeen
+                    ? colorScheme.primary
+                    : null,
+              ),
+              const SizedBox(width: 8),
+              Text(l10n.lastSeen),
+            ],
+          ),
+        ),
+        PopupMenuItem<ContactSortMode>(
+          value: ContactSortMode.distance,
+          child: Row(
+            children: [
+              Icon(
+                Icons.near_me,
+                size: 18,
+                color: selectedMode == ContactSortMode.distance
+                    ? colorScheme.primary
+                    : null,
+              ),
+              const SizedBox(width: 8),
+              Text(l10n.distance),
+            ],
+          ),
+        ),
+      ],
+      child: Padding(
+        padding: const EdgeInsets.all(4),
+        child: Icon(
+          Icons.more_horiz,
+          size: 18,
+          color: colorScheme.onSurfaceVariant,
+        ),
+      ),
+    );
+  }
 }
 
+enum ContactSortMode { lastSeen, distance }
+
+enum ContactSection { teamMembers, repeaters, rooms, channels }
+
 class _PendingAdvertTile extends StatelessWidget {
   final PendingAdvert advert;
   final String subtitle;
@@ -377,11 +525,13 @@ class _SectionHeader extends StatelessWidget {
   final String title;
   final int count;
   final IconData icon;
+  final Widget? trailing;
 
   const _SectionHeader({
     required this.title,
     required this.count,
     required this.icon,
+    this.trailing,
   });
 
   @override
@@ -410,6 +560,454 @@ class _SectionHeader extends StatelessWidget {
               style: Theme.of(context).textTheme.labelSmall,
             ),
           ),
+          if (trailing != null) ...[const Spacer(), trailing!],
+        ],
+      ),
+    );
+  }
+}
+
+class _InferredContactGroupCard extends StatelessWidget {
+  final String label;
+  final List<Contact> contacts;
+  final Position? currentPosition;
+  final double Function(double, double, double, double) calculateDistance;
+  final String Function(double) formatDistance;
+  final VoidCallback? onNavigateToMap;
+  final VoidCallback? onNavigateToMessages;
+
+  const _InferredContactGroupCard({
+    required this.label,
+    required this.contacts,
+    required this.currentPosition,
+    required this.calculateDistance,
+    required this.formatDistance,
+    required this.onNavigateToMap,
+    required this.onNavigateToMessages,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+
+    return Container(
+      margin: const EdgeInsets.only(bottom: 12),
+      decoration: BoxDecoration(
+        color: colorScheme.surfaceContainerLow,
+        borderRadius: BorderRadius.circular(18),
+        border: Border.all(
+          color: colorScheme.outlineVariant.withValues(alpha: 0.35),
+        ),
+      ),
+      child: Theme(
+        data: Theme.of(context).copyWith(dividerColor: Colors.transparent),
+        child: ExpansionTile(
+          tilePadding: const EdgeInsets.symmetric(horizontal: 12, vertical: 2),
+          childrenPadding: const EdgeInsets.fromLTRB(12, 0, 12, 8),
+          initiallyExpanded: false,
+          leading: Icon(
+            Icons.folder_copy_outlined,
+            size: 18,
+            color: colorScheme.primary,
+          ),
+          title: Row(
+            children: [
+              Expanded(
+                child: Text(
+                  label,
+                  style: Theme.of(
+                    context,
+                  ).textTheme.titleSmall?.copyWith(fontWeight: FontWeight.w800),
+                ),
+              ),
+              const SizedBox(width: 8),
+              Container(
+                padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 2),
+                decoration: BoxDecoration(
+                  color: colorScheme.primaryContainer,
+                  borderRadius: BorderRadius.circular(999),
+                ),
+                child: Text(
+                  contacts.length.toString(),
+                  style: Theme.of(context).textTheme.labelSmall,
+                ),
+              ),
+            ],
+          ),
+          children: [
+            ...contacts.map(
+              (contact) => ContactTile(
+                contact: contact,
+                currentPosition: currentPosition,
+                calculateDistance: calculateDistance,
+                formatDistance: formatDistance,
+                onNavigateToMap: onNavigateToMap,
+                onNavigateToMessages: onNavigateToMessages,
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class _ChannelActivityCard extends StatelessWidget {
+  final Contact channel;
+  final MessagesProvider messagesProvider;
+  final ContactsProvider contactsProvider;
+  final VoidCallback? onNavigateToMessages;
+
+  const _ChannelActivityCard({
+    required this.channel,
+    required this.messagesProvider,
+    required this.contactsProvider,
+    required this.onNavigateToMessages,
+  });
+
+  String _formatRelativeTime(BuildContext context, DateTime when) {
+    final l10n = AppLocalizations.of(context)!;
+    final diff = DateTime.now().difference(when);
+
+    if (diff.inMinutes < 1) return l10n.justNow;
+    if (diff.inMinutes < 60) return l10n.minutesAgo(diff.inMinutes);
+    if (diff.inHours < 24) return l10n.hoursAgo(diff.inHours);
+    return l10n.daysAgo(diff.inDays);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+    final titleStyle = Theme.of(context).textTheme.titleMedium?.copyWith(
+      fontWeight: FontWeight.w800,
+      letterSpacing: -0.3,
+    );
+    final channelIdx = channel.publicKey.length > 1 ? channel.publicKey[1] : 0;
+    final channelMessages = messagesProvider.getMessagesForChannel(channelIdx)
+      ..sort((a, b) => b.sentAt.compareTo(a.sentAt));
+    final lastActivityAt = messagesProvider.getLastActivityForDestination(
+      channel,
+    );
+    final activityLabel = lastActivityAt == null
+        ? null
+        : _formatRelativeTime(context, lastActivityAt);
+    final participantNames = <String>[];
+    for (final message in channelMessages) {
+      final senderName = message.senderName?.trim();
+      if (senderName == null || senderName.isEmpty) continue;
+      if (!participantNames.contains(senderName)) {
+        participantNames.add(senderName);
+      }
+    }
+    return Container(
+      margin: const EdgeInsets.only(bottom: 8),
+      decoration: BoxDecoration(
+        borderRadius: BorderRadius.circular(18),
+        gradient: LinearGradient(
+          begin: Alignment.topLeft,
+          end: Alignment.bottomRight,
+          colors: [
+            colorScheme.surfaceContainerLow,
+            colorScheme.surfaceContainerHighest.withValues(alpha: 0.9),
+          ],
+        ),
+        border: Border.all(
+          color: colorScheme.outlineVariant.withValues(alpha: 0.35),
+        ),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withValues(alpha: 0.045),
+            blurRadius: 12,
+            offset: const Offset(0, 4),
+          ),
+        ],
+      ),
+      child: Material(
+        color: Colors.transparent,
+        child: InkWell(
+          borderRadius: BorderRadius.circular(18),
+          onTap: () async {
+            await MessageDestinationPreferences.setDestination(
+              MessageDestinationPreferences.destinationTypeChannel,
+              recipientPublicKey: channel.publicKeyHex,
+            );
+            messagesProvider.navigateToDestination(
+              MessageDestinationPreferences.destinationTypeChannel,
+              recipientPublicKeyHex: channel.publicKeyHex,
+            );
+            onNavigateToMessages?.call();
+          },
+          child: Padding(
+            padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
+            child: Row(
+              crossAxisAlignment: CrossAxisAlignment.center,
+              children: [
+                ContactAvatar(contact: channel, radius: 24),
+                const SizedBox(width: 10),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Row(
+                        crossAxisAlignment: CrossAxisAlignment.start,
+                        children: [
+                          Expanded(
+                            child: Text(
+                              channel.displayName,
+                              maxLines: 1,
+                              overflow: TextOverflow.ellipsis,
+                              style: titleStyle,
+                            ),
+                          ),
+                          const SizedBox(width: 8),
+                          if (activityLabel != null)
+                            Text(
+                              activityLabel,
+                              style: Theme.of(context).textTheme.labelSmall
+                                  ?.copyWith(
+                                    color: colorScheme.onSurfaceVariant,
+                                    fontWeight: FontWeight.w600,
+                                  ),
+                            ),
+                        ],
+                      ),
+                      const SizedBox(height: 8),
+                      if (participantNames.isNotEmpty)
+                        _ExpandableParticipantStack(
+                          names: participantNames,
+                          contactForName: _findParticipantContact,
+                        )
+                      else
+                        Text(
+                          'No recent chatters',
+                          style: Theme.of(context).textTheme.bodySmall
+                              ?.copyWith(color: colorScheme.onSurfaceVariant),
+                        ),
+                      const SizedBox(height: 8),
+                      Wrap(
+                        spacing: 6,
+                        runSpacing: 6,
+                        children: [
+                          _MetricChip(
+                            icon: Icons.forum_outlined,
+                            label: '${channelMessages.length}',
+                            helper: 'messages',
+                          ),
+                          _MetricChip(
+                            icon: Icons.group_outlined,
+                            label: '${participantNames.length}',
+                            helper: 'active',
+                          ),
+                        ],
+                      ),
+                    ],
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  Contact? _findParticipantContact(String name) {
+    for (final contact in contactsProvider.contacts) {
+      if (!contact.isChannel && contact.advName == name) {
+        return contact;
+      }
+    }
+    return null;
+  }
+}
+
+class _ExpandableParticipantStack extends StatefulWidget {
+  final List<String> names;
+  final Contact? Function(String name) contactForName;
+
+  const _ExpandableParticipantStack({
+    required this.names,
+    required this.contactForName,
+  });
+
+  @override
+  State<_ExpandableParticipantStack> createState() =>
+      _ExpandableParticipantStackState();
+}
+
+class _ExpandableParticipantStackState
+    extends State<_ExpandableParticipantStack> {
+  bool _expanded = false;
+  static const int _collapsedVisibleCount = 4;
+
+  @override
+  Widget build(BuildContext context) {
+    final hasOverflow = widget.names.length > _collapsedVisibleCount;
+    final visibleNames = _expanded
+        ? widget.names
+        : widget.names.take(_collapsedVisibleCount).toList();
+    final overflowCount = _expanded
+        ? 0
+        : widget.names.length - visibleNames.length;
+    final spacing = _expanded ? 20.0 : 16.0;
+    const avatarSize = 24.0;
+    final itemCount = visibleNames.length + (overflowCount > 0 ? 1 : 0);
+    final width = itemCount == 0 ? 0.0 : avatarSize + (itemCount - 1) * spacing;
+
+    return GestureDetector(
+      onTap: hasOverflow
+          ? () {
+              setState(() {
+                _expanded = !_expanded;
+              });
+            }
+          : null,
+      child: AnimatedContainer(
+        duration: const Duration(milliseconds: 180),
+        curve: Curves.easeOut,
+        width: width,
+        height: avatarSize,
+        child: Stack(
+          clipBehavior: Clip.none,
+          children: [
+            for (var i = 0; i < visibleNames.length; i++)
+              Positioned(
+                left: i * spacing,
+                top: 0,
+                child: _ParticipantAvatar(
+                  name: visibleNames[i],
+                  contact: widget.contactForName(visibleNames[i]),
+                ),
+              ),
+            if (overflowCount > 0)
+              Positioned(
+                left: visibleNames.length * spacing,
+                top: 0,
+                child: _OverflowAvatar(count: overflowCount),
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class _OverflowAvatar extends StatelessWidget {
+  final int count;
+
+  const _OverflowAvatar({required this.count});
+
+  @override
+  Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+    return Container(
+      width: 24,
+      height: 24,
+      decoration: BoxDecoration(
+        color: colorScheme.surfaceContainerHighest,
+        shape: BoxShape.circle,
+        border: Border.all(color: colorScheme.surface, width: 2),
+      ),
+      alignment: Alignment.center,
+      child: Text(
+        '+$count',
+        style: Theme.of(context).textTheme.labelSmall?.copyWith(
+          fontWeight: FontWeight.w700,
+          color: colorScheme.onSurface,
+          fontSize: 9,
+        ),
+      ),
+    );
+  }
+}
+
+class _ParticipantAvatar extends StatelessWidget {
+  final String name;
+  final Contact? contact;
+  static const double _size = 24;
+
+  const _ParticipantAvatar({required this.name, required this.contact});
+
+  @override
+  Widget build(BuildContext context) {
+    if (contact != null) {
+      final surfaceColor = Theme.of(context).colorScheme.surface;
+      return SizedBox(
+        width: _size,
+        height: _size,
+        child: DecoratedBox(
+          decoration: BoxDecoration(
+            shape: BoxShape.circle,
+            border: Border.all(color: surfaceColor, width: 2),
+          ),
+          child: Padding(
+            padding: const EdgeInsets.all(2),
+            child: ClipOval(child: ContactAvatar(contact: contact!, radius: 8)),
+          ),
+        ),
+      );
+    }
+
+    final colorScheme = Theme.of(context).colorScheme;
+    return Container(
+      width: _size,
+      height: _size,
+      decoration: BoxDecoration(
+        color: colorScheme.tertiaryContainer,
+        shape: BoxShape.circle,
+        border: Border.all(color: colorScheme.surface, width: 2),
+      ),
+      alignment: Alignment.center,
+      child: Text(
+        AvatarLabelHelper.buildLabel(name),
+        style: Theme.of(context).textTheme.labelSmall?.copyWith(
+          fontWeight: FontWeight.w700,
+          color: colorScheme.onTertiaryContainer,
+          fontSize: 9,
+        ),
+      ),
+    );
+  }
+}
+
+class _MetricChip extends StatelessWidget {
+  final IconData icon;
+  final String label;
+  final String helper;
+
+  const _MetricChip({
+    required this.icon,
+    required this.label,
+    required this.helper,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 7, vertical: 4),
+      decoration: BoxDecoration(
+        color: colorScheme.surface.withValues(alpha: 0.72),
+        borderRadius: BorderRadius.circular(999),
+      ),
+      child: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          Icon(icon, size: 14, color: colorScheme.onSurfaceVariant),
+          const SizedBox(width: 5),
+          Text(
+            label,
+            style: Theme.of(
+              context,
+            ).textTheme.labelSmall?.copyWith(fontWeight: FontWeight.w700),
+          ),
+          const SizedBox(width: 4),
+          Text(
+            helper,
+            style: Theme.of(context).textTheme.labelSmall?.copyWith(
+              color: colorScheme.onSurfaceVariant,
+            ),
+          ),
         ],
       ),
     );

lib/screens/device_config_screen.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
-import 'package:provider/provider.dart';
 import 'package:geolocator/geolocator.dart';
+import 'package:provider/provider.dart';
 import '../providers/connection_provider.dart';
 import '../services/validation_service.dart';
 import '../l10n/app_localizations.dart';
@@ -398,26 +398,51 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
   Widget build(BuildContext context) {
     final deviceInfo = context.watch<ConnectionProvider>().deviceInfo;
     final theme = Theme.of(context);
+    final colorScheme = theme.colorScheme;
+    final locationSet =
+        (deviceInfo.advLat != null && deviceInfo.advLat != 0) ||
+        (deviceInfo.advLon != null && deviceInfo.advLon != 0);
 
     return Scaffold(
       appBar: AppBar(title: Text(AppLocalizations.of(context)!.settings)),
-      body: ListView(
-        padding: const EdgeInsets.all(16),
-        children: [
-          // Device Info Card
-          Card(
-            child: Padding(
-              padding: const EdgeInsets.all(16),
+      body: SafeArea(
+        child: ListView(
+          padding: const EdgeInsets.fromLTRB(16, 12, 16, 24),
+          children: [
+            _ConfigHeroCard(
+              title: deviceInfo.selfName ?? deviceInfo.deviceName ?? 'MeshCore',
+              subtitle:
+                  '${_getDeviceTypeString(context, deviceInfo.deviceType)} • ${deviceInfo.semanticVersion ?? deviceInfo.manufacturerModel ?? AppLocalizations.of(context)!.unknown}',
+              chips: [
+                _StatusChipData(
+                  icon: Icons.bluetooth,
+                  label:
+                      '${AppLocalizations.of(context)!.bleName}: ${deviceInfo.deviceName ?? AppLocalizations.of(context)!.unknown}',
+                ),
+                _StatusChipData(
+                  icon: Icons.my_location,
+                  label: locationSet ? 'Location ready' : 'Location off',
+                  emphasized: locationSet,
+                ),
+                _StatusChipData(
+                  icon: Icons.settings_input_antenna,
+                  label: '${_freqController.text} MHz • $_selectedBandwidth',
+                ),
+                _StatusChipData(
+                  icon: Icons.key,
+                  label: 'FW v${deviceInfo.firmwareVersion?.toString() ?? "?"}',
+                ),
+              ],
+            ),
+            const SizedBox(height: 20),
+            _ConfigSectionCard(
+              title: AppLocalizations.of(context)!.deviceInformation,
+              subtitle:
+                  '${deviceInfo.manufacturerModel ?? AppLocalizations.of(context)!.unknown} • ${deviceInfo.firmwareBuildDate ?? AppLocalizations.of(context)!.unknown}',
+              icon: Icons.memory_rounded,
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
-                  Text(
-                    AppLocalizations.of(context)!.deviceInformation,
-                    style: theme.textTheme.titleLarge?.copyWith(
-                      fontWeight: FontWeight.bold,
-                    ),
-                  ),
-                  const SizedBox(height: 16),
                   _InfoRow(
                     AppLocalizations.of(context)!.bleName,
                     deviceInfo.deviceName ??
@@ -467,42 +492,75 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                 ],
               ),
             ),
-          ),
-
-          const SizedBox(height: 24),
-
-          // Public Info Section
-          Card(
-            child: Padding(
-              padding: const EdgeInsets.all(16),
+            const SizedBox(height: 20),
+            _ConfigSectionCard(
+              title: AppLocalizations.of(context)!.publicInfo,
+              subtitle: AppLocalizations.of(context)!.nameBroadcastInMesh,
+              icon: Icons.public_rounded,
+              trailing: FilledButton.icon(
+                onPressed: _savePublicInfo,
+                icon: const Icon(Icons.save_outlined),
+                label: Text(AppLocalizations.of(context)!.save),
+              ),
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
-                  Row(
-                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
-                    children: [
-                      Text(
-                        AppLocalizations.of(context)!.publicInfo,
-                        style: theme.textTheme.titleLarge?.copyWith(
-                          fontWeight: FontWeight.bold,
+                  Container(
+                    padding: const EdgeInsets.all(14),
+                    decoration: BoxDecoration(
+                      color: colorScheme.surfaceContainerHighest.withValues(
+                        alpha: 0.45,
+                      ),
+                      borderRadius: BorderRadius.circular(18),
+                    ),
+                    child: Row(
+                      children: [
+                        Icon(
+                          _telemetryEnabled
+                              ? Icons.travel_explore
+                              : Icons.location_disabled,
+                          color: _telemetryEnabled
+                              ? colorScheme.primary
+                              : colorScheme.onSurfaceVariant,
                         ),
-                      ),
-                      Row(
-                        mainAxisSize: MainAxisSize.min,
-                        children: [
-                          const SizedBox(width: 8),
-                          IconButton.filled(
-                            onPressed: _savePublicInfo,
-                            icon: const Icon(Icons.save),
-                            tooltip: AppLocalizations.of(context)!.save,
+                        const SizedBox(width: 12),
+                        Expanded(
+                          child: Column(
+                            crossAxisAlignment: CrossAxisAlignment.start,
+                            children: [
+                              Text(
+                                AppLocalizations.of(
+                                  context,
+                                )!.telemetryAndLocationSharing,
+                                style: theme.textTheme.titleSmall?.copyWith(
+                                  fontWeight: FontWeight.w700,
+                                ),
+                              ),
+                              const SizedBox(height: 2),
+                              Text(
+                                _telemetryEnabled
+                                    ? 'This device advertises position data to the mesh.'
+                                    : 'Position broadcasting is currently disabled.',
+                                style: theme.textTheme.bodySmall?.copyWith(
+                                  color: colorScheme.onSurfaceVariant,
+                                ),
+                              ),
+                            ],
                           ),
-                        ],
-                      ),
-                    ],
+                        ),
+                        const SizedBox(width: 12),
+                        Switch(
+                          value: _telemetryEnabled,
+                          onChanged: (value) {
+                            setState(() {
+                              _telemetryEnabled = value;
+                            });
+                          },
+                        ),
+                      ],
+                    ),
                   ),
-                  const SizedBox(height: 16),
-
-                  // Mesh Network Name
+                  const SizedBox(height: 18),
                   TextField(
                     controller: _nameController,
                     decoration: InputDecoration(
@@ -513,62 +571,21 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                       )!.nameBroadcastInMesh,
                     ),
                   ),
-                  const SizedBox(height: 8),
-
-                  // Telemetry Toggle - Compact version
-                  Row(
-                    children: [
-                      Expanded(
-                        child: Text(
-                          AppLocalizations.of(
-                            context,
-                          )!.telemetryAndLocationSharing,
-                          style: theme.textTheme.bodyMedium,
-                        ),
-                      ),
-                      Switch(
-                        value: _telemetryEnabled,
-                        onChanged: (value) {
-                          setState(() {
-                            _telemetryEnabled = value;
-                          });
-                        },
-                      ),
-                    ],
-                  ),
-
-                  // GPS Coordinates (only show if telemetry enabled)
                   if (_telemetryEnabled) ...[
-                    const SizedBox(height: 12),
+                    const SizedBox(height: 16),
                     Row(
                       children: [
                         Expanded(
-                          child: TextField(
+                          child: _CompactCoordinateField(
                             controller: _latController,
-                            decoration: InputDecoration(
-                              labelText: AppLocalizations.of(context)!.lat,
-                              border: const OutlineInputBorder(),
-                              isDense: true,
-                            ),
-                            keyboardType: const TextInputType.numberWithOptions(
-                              decimal: true,
-                              signed: true,
-                            ),
+                            label: AppLocalizations.of(context)!.lat,
                           ),
                         ),
                         const SizedBox(width: 8),
                         Expanded(
-                          child: TextField(
+                          child: _CompactCoordinateField(
                             controller: _lonController,
-                            decoration: InputDecoration(
-                              labelText: AppLocalizations.of(context)!.lon,
-                              border: const OutlineInputBorder(),
-                              isDense: true,
-                            ),
-                            keyboardType: const TextInputType.numberWithOptions(
-                              decimal: true,
-                              signed: true,
-                            ),
+                            label: AppLocalizations.of(context)!.lon,
                           ),
                         ),
                         const SizedBox(width: 8),
@@ -585,36 +602,45 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                 ],
               ),
             ),
-          ),
-
-          const SizedBox(height: 24),
-
-          // Radio Settings Section
-          Card(
-            child: Padding(
-              padding: const EdgeInsets.all(16),
+            const SizedBox(height: 20),
+            _ConfigSectionCard(
+              title: AppLocalizations.of(context)!.radioSettings,
+              subtitle:
+                  '${_freqController.text} MHz • SF$_selectedSpreadingFactor • CR$_selectedCodingRate',
+              icon: Icons.settings_input_antenna_rounded,
+              trailing: FilledButton.icon(
+                onPressed: _saveRadioSettings,
+                icon: const Icon(Icons.save_outlined),
+                label: Text(AppLocalizations.of(context)!.save),
+              ),
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
                   Row(
-                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                     children: [
-                      Text(
-                        AppLocalizations.of(context)!.radioSettings,
-                        style: theme.textTheme.titleLarge?.copyWith(
-                          fontWeight: FontWeight.bold,
+                      Expanded(
+                        child: _RadioMetricTile(
+                          label: AppLocalizations.of(context)!.bandwidth,
+                          value: _selectedBandwidth,
                         ),
                       ),
-                      IconButton.filled(
-                        onPressed: _saveRadioSettings,
-                        icon: const Icon(Icons.save),
-                        tooltip: AppLocalizations.of(context)!.save,
+                      const SizedBox(width: 10),
+                      Expanded(
+                        child: _RadioMetricTile(
+                          label: AppLocalizations.of(context)!.spreadingFactor,
+                          value: 'SF$_selectedSpreadingFactor',
+                        ),
+                      ),
+                      const SizedBox(width: 10),
+                      Expanded(
+                        child: _RadioMetricTile(
+                          label: AppLocalizations.of(context)!.codingRate,
+                          value: 'CR$_selectedCodingRate',
+                        ),
                       ),
                     ],
                   ),
                   const SizedBox(height: 16),
-
-                  // LoRa Frequency
                   TextField(
                     controller: _freqController,
                     decoration: InputDecoration(
@@ -629,8 +655,6 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                     ),
                   ),
                   const SizedBox(height: 16),
-
-                  // Bandwidth
                   DropdownButtonFormField<String>(
                     initialValue: _selectedBandwidth,
                     decoration: InputDecoration(
@@ -652,8 +676,6 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                     },
                   ),
                   const SizedBox(height: 16),
-
-                  // Spreading Factor
                   DropdownButtonFormField<int>(
                     initialValue: _selectedSpreadingFactor,
                     decoration: InputDecoration(
@@ -677,8 +699,6 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                     },
                   ),
                   const SizedBox(height: 16),
-
-                  // Coding Rate
                   DropdownButtonFormField<int>(
                     initialValue: _selectedCodingRate,
                     decoration: InputDecoration(
@@ -702,8 +722,6 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                     },
                   ),
                   const SizedBox(height: 16),
-
-                  // TX Power
                   TextField(
                     controller: _txPowerController,
                     decoration: InputDecoration(
@@ -715,36 +733,42 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
                     ),
                     keyboardType: TextInputType.number,
                   ),
-
-                  // Repeat Mode (firmware v9+)
                   if (deviceInfo.clientRepeat != null) ...[
-                    const SizedBox(height: 8),
-                    SwitchListTile(
-                      contentPadding: EdgeInsets.zero,
-                      title: const Text('Client Repeat Mode'),
-                      subtitle: deviceInfo.allowedRepeatFreqRanges != null &&
-                              deviceInfo.allowedRepeatFreqRanges!.isNotEmpty
-                          ? Text(
-                              'Allowed: ${deviceInfo.allowedRepeatFreqRanges!.map((r) => r.lower == r.upper ? '${(r.lower / 1000).toStringAsFixed(3)} MHz' : '${(r.lower / 1000).toStringAsFixed(3)}–${(r.upper / 1000).toStringAsFixed(3)} MHz').join(', ')}',
-                            )
-                          : const Text(
-                              'Repeat packets on behalf of nearby nodes',
-                            ),
-                      value: _repeatEnabled,
-                      onChanged: (value) {
-                        setState(() {
-                          _repeatEnabled = value;
-                        });
-                      },
+                    const SizedBox(height: 16),
+                    Container(
+                      padding: const EdgeInsets.all(14),
+                      decoration: BoxDecoration(
+                        color: colorScheme.surfaceContainerHighest.withValues(
+                          alpha: 0.45,
+                        ),
+                        borderRadius: BorderRadius.circular(18),
+                      ),
+                      child: SwitchListTile(
+                        contentPadding: EdgeInsets.zero,
+                        title: const Text('Client Repeat Mode'),
+                        subtitle:
+                            deviceInfo.allowedRepeatFreqRanges != null &&
+                                deviceInfo.allowedRepeatFreqRanges!.isNotEmpty
+                            ? Text(
+                                'Allowed: ${deviceInfo.allowedRepeatFreqRanges!.map((r) => r.lower == r.upper ? '${(r.lower / 1000).toStringAsFixed(3)} MHz' : '${(r.lower / 1000).toStringAsFixed(3)}–${(r.upper / 1000).toStringAsFixed(3)} MHz').join(', ')}',
+                              )
+                            : const Text(
+                                'Repeat packets on behalf of nearby nodes',
+                              ),
+                        value: _repeatEnabled,
+                        onChanged: (value) {
+                          setState(() {
+                            _repeatEnabled = value;
+                          });
+                        },
+                      ),
                     ),
                   ],
                 ],
               ),
             ),
-          ),
-
-          const SizedBox(height: 24),
-        ],
+          ],
+        ),
       ),
     );
   }
@@ -771,6 +795,276 @@ class _DeviceConfigScreenState extends State<DeviceConfigScreen> {
   }
 }
 
+class _ConfigHeroCard extends StatelessWidget {
+  final String title;
+  final String subtitle;
+  final List<_StatusChipData> chips;
+
+  const _ConfigHeroCard({
+    required this.title,
+    required this.subtitle,
+    required this.chips,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final colorScheme = theme.colorScheme;
+
+    return Container(
+      padding: const EdgeInsets.all(20),
+      decoration: BoxDecoration(
+        gradient: LinearGradient(
+          colors: [
+            colorScheme.primaryContainer,
+            colorScheme.surfaceContainerHighest,
+          ],
+          begin: Alignment.topLeft,
+          end: Alignment.bottomRight,
+        ),
+        borderRadius: BorderRadius.circular(28),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Row(
+            children: [
+              Container(
+                width: 52,
+                height: 52,
+                decoration: BoxDecoration(
+                  color: colorScheme.onPrimaryContainer.withValues(alpha: 0.12),
+                  borderRadius: BorderRadius.circular(18),
+                ),
+                child: Icon(
+                  Icons.tune_rounded,
+                  color: colorScheme.onPrimaryContainer,
+                ),
+              ),
+              const SizedBox(width: 14),
+              Expanded(
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    Text(
+                      title,
+                      style: theme.textTheme.headlineSmall?.copyWith(
+                        fontWeight: FontWeight.w800,
+                        color: colorScheme.onPrimaryContainer,
+                      ),
+                    ),
+                    const SizedBox(height: 4),
+                    Text(
+                      subtitle,
+                      style: theme.textTheme.bodyMedium?.copyWith(
+                        color: colorScheme.onPrimaryContainer.withValues(
+                          alpha: 0.82,
+                        ),
+                      ),
+                    ),
+                  ],
+                ),
+              ),
+            ],
+          ),
+          const SizedBox(height: 18),
+          Wrap(
+            spacing: 10,
+            runSpacing: 10,
+            children: chips.map(_StatusChip.new).toList(),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class _ConfigSectionCard extends StatelessWidget {
+  final String title;
+  final String subtitle;
+  final IconData icon;
+  final Widget child;
+  final Widget? trailing;
+
+  const _ConfigSectionCard({
+    required this.title,
+    required this.subtitle,
+    required this.icon,
+    required this.child,
+    this.trailing,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final colorScheme = theme.colorScheme;
+
+    return Card(
+      clipBehavior: Clip.antiAlias,
+      child: Padding(
+        padding: const EdgeInsets.all(18),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Row(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Container(
+                  width: 42,
+                  height: 42,
+                  decoration: BoxDecoration(
+                    color: colorScheme.primary.withValues(alpha: 0.10),
+                    borderRadius: BorderRadius.circular(14),
+                  ),
+                  child: Icon(icon, color: colorScheme.primary),
+                ),
+                const SizedBox(width: 12),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Text(
+                        title,
+                        style: theme.textTheme.titleLarge?.copyWith(
+                          fontWeight: FontWeight.w800,
+                        ),
+                      ),
+                      const SizedBox(height: 3),
+                      Text(
+                        subtitle,
+                        style: theme.textTheme.bodySmall?.copyWith(
+                          color: colorScheme.onSurfaceVariant,
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+                if (trailing != null) ...[const SizedBox(width: 12), trailing!],
+              ],
+            ),
+            const SizedBox(height: 18),
+            child,
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class _StatusChipData {
+  final IconData icon;
+  final String label;
+  final bool emphasized;
+
+  const _StatusChipData({
+    required this.icon,
+    required this.label,
+    this.emphasized = false,
+  });
+}
+
+class _StatusChip extends StatelessWidget {
+  final _StatusChipData data;
+
+  const _StatusChip(this.data);
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final colorScheme = theme.colorScheme;
+    final chipColor = data.emphasized
+        ? colorScheme.primary.withValues(alpha: 0.14)
+        : colorScheme.onPrimaryContainer.withValues(alpha: 0.10);
+
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
+      decoration: BoxDecoration(
+        color: chipColor,
+        borderRadius: BorderRadius.circular(999),
+      ),
+      child: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          Icon(data.icon, size: 16, color: colorScheme.onPrimaryContainer),
+          const SizedBox(width: 8),
+          Text(
+            data.label,
+            style: theme.textTheme.labelLarge?.copyWith(
+              color: colorScheme.onPrimaryContainer,
+              fontWeight: FontWeight.w700,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class _CompactCoordinateField extends StatelessWidget {
+  final TextEditingController controller;
+  final String label;
+
+  const _CompactCoordinateField({
+    required this.controller,
+    required this.label,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return TextField(
+      controller: controller,
+      decoration: InputDecoration(
+        labelText: label,
+        border: const OutlineInputBorder(),
+        isDense: true,
+      ),
+      keyboardType: const TextInputType.numberWithOptions(
+        decimal: true,
+        signed: true,
+      ),
+    );
+  }
+}
+
+class _RadioMetricTile extends StatelessWidget {
+  final String label;
+  final String value;
+
+  const _RadioMetricTile({required this.label, required this.value});
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final colorScheme = theme.colorScheme;
+
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 14),
+      decoration: BoxDecoration(
+        color: colorScheme.surfaceContainerHighest.withValues(alpha: 0.45),
+        borderRadius: BorderRadius.circular(18),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            label,
+            style: theme.textTheme.labelMedium?.copyWith(
+              color: colorScheme.onSurfaceVariant,
+            ),
+          ),
+          const SizedBox(height: 6),
+          Text(
+            value,
+            style: theme.textTheme.titleMedium?.copyWith(
+              fontWeight: FontWeight.w800,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
 class _InfoRow extends StatelessWidget {
   final String label;
   final String value;

lib/screens/packet_log_screen.dart

@@ -1,10 +1,16 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
+import 'package:provider/provider.dart';
 import 'package:share_plus/share_plus.dart';
 import 'dart:io';
 import 'package:path_provider/path_provider.dart';
 import 'package:meshcore_client/meshcore_client.dart';
 import '../l10n/app_localizations.dart';
+import '../providers/connection_provider.dart';
+import '../providers/contacts_provider.dart';
+import '../services/mesh_map_nodes_service.dart';
+import '../services/route_hash_preferences.dart';
+import '../utils/log_rx_route_decoder.dart';
 
 class PacketLogScreen extends StatefulWidget {
   final MeshCoreBleService bleService;
@@ -580,6 +586,10 @@ class _PacketLogCard extends StatelessWidget {
                     ),
                   ),
                 ],
+                if (isRx) ...[
+                  const SizedBox(height: 12),
+                  _DecodedRouteSection(log: log),
+                ],
                 const SizedBox(height: 12),
                 Container(
                   padding: const EdgeInsets.all(12),
@@ -723,6 +733,259 @@ class _PacketLogCard extends StatelessWidget {
   }
 }
 
+class _DecodedRouteSection extends StatelessWidget {
+  final BlePacketLog log;
+
+  const _DecodedRouteSection({required this.log});
+
+  @override
+  Widget build(BuildContext context) {
+    final contacts = context.watch<ContactsProvider>().contacts;
+    final connectionProvider = context.watch<ConnectionProvider>();
+    final ownPublicKey = connectionProvider.deviceInfo.publicKey;
+    final ownName =
+        connectionProvider.deviceInfo.selfName ??
+        connectionProvider.deviceInfo.displayName;
+
+    return FutureBuilder<List<dynamic>>(
+      future: Future.wait<dynamic>([
+        RouteHashPreferences.getHashSize(),
+        MeshMapNodesService.loadCachedNodes(
+          cacheTtl: MeshMapNodesService.traceCacheTtl,
+        ),
+      ]),
+      builder: (context, snapshot) {
+        final decodedRoute = LogRxRouteDecoder.decode(
+          log.rawData,
+          preferredHashSize: snapshot.data?.first as int?,
+        );
+        if (decodedRoute == null) {
+          return const SizedBox.shrink();
+        }
+
+        final cachedNodes = snapshot.hasData
+            ? snapshot.data![1] as List<MeshMapNode>
+            : const <MeshMapNode>[];
+        final resolvedPath = decodedRoute.hopHashes
+            .map(
+              (hashHex) => _resolveHashWithFallback(
+                hashHex,
+                contacts: contacts,
+                cachedNodes: cachedNodes,
+                ownPublicKey: ownPublicKey,
+                ownName: ownName,
+              ),
+            )
+            .toList();
+        final originalSender = resolvedPath.isEmpty ? null : resolvedPath.first;
+
+        return _RouteSection(
+          route: decodedRoute,
+          path: resolvedPath,
+          originalSender: originalSender,
+        );
+      },
+    );
+  }
+
+  ResolvedNodeHash _resolveHashWithFallback(
+    String hashHex, {
+    required List<Contact> contacts,
+    required List<MeshMapNode> cachedNodes,
+    required Uint8List? ownPublicKey,
+    required String? ownName,
+  }) {
+    final localResolved = LogRxRouteDecoder.resolveHash(
+      hashHex,
+      contacts: contacts,
+      ownPublicKey: ownPublicKey,
+      ownName: ownName,
+    );
+    if (localResolved.matchCount > 0 || localResolved.isOwnNode) {
+      return localResolved;
+    }
+
+    final normalizedHashHex = hashHex.toLowerCase();
+    final matches = cachedNodes
+        .where((node) => node.publicKey.startsWith(normalizedHashHex))
+        .toList();
+    if (matches.isEmpty) {
+      return localResolved;
+    }
+
+    matches.sort((a, b) => b.updatedAtMs.compareTo(a.updatedAtMs));
+    return ResolvedNodeHash(
+      hashHex: normalizedHashHex,
+      label: matches.first.name,
+      isOwnNode: false,
+      isUniqueMatch: matches.length == 1,
+      matchCount: matches.length,
+    );
+  }
+}
+
+class _RouteSection extends StatelessWidget {
+  final DecodedLogRxRoute route;
+  final List<ResolvedNodeHash> path;
+  final ResolvedNodeHash? originalSender;
+
+  const _RouteSection({
+    required this.route,
+    required this.path,
+    required this.originalSender,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      padding: const EdgeInsets.all(12),
+      decoration: BoxDecoration(
+        color: Theme.of(
+          context,
+        ).colorScheme.surfaceContainerHighest.withValues(alpha: 0.5),
+        borderRadius: BorderRadius.circular(10),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          const Row(
+            children: [
+              Icon(Icons.alt_route, size: 16),
+              SizedBox(width: 6),
+              Text(
+                'Mesh Route',
+                style: TextStyle(fontWeight: FontWeight.w700, fontSize: 12),
+              ),
+            ],
+          ),
+          const SizedBox(height: 10),
+          Wrap(
+            spacing: 10,
+            runSpacing: 10,
+            children: [
+              _FactCard(
+                icon: Icons.route,
+                label: 'Payload',
+                value: _payloadTypeLabel(route.payloadType),
+              ),
+              _FactCard(
+                icon: Icons.hub,
+                label: 'Hops',
+                value: '${route.hopCount}',
+              ),
+              _FactCard(
+                icon: Icons.tag,
+                label: 'Hash size',
+                value:
+                    '${route.hashSize} byte${route.hashSize == 1 ? '' : 's'}',
+              ),
+              if (originalSender != null)
+                _FactCard(
+                  icon: Icons.person_pin_circle,
+                  label: 'Original sender',
+                  value: _nodeLabel(originalSender!),
+                ),
+            ],
+          ),
+          const SizedBox(height: 12),
+          if (path.isEmpty)
+            Text(
+              'Direct packet, no hop path attached.',
+              style: TextStyle(fontSize: 12, color: Colors.grey[700]),
+            )
+          else
+            Wrap(
+              spacing: 6,
+              runSpacing: 6,
+              children: [
+                for (var i = 0; i < path.length; i++) ...[
+                  _RouteHopChip(index: i + 1, node: path[i]),
+                  if (i < path.length - 1)
+                    const Padding(
+                      padding: EdgeInsets.symmetric(horizontal: 2),
+                      child: Icon(Icons.arrow_right_alt, size: 16),
+                    ),
+                ],
+              ],
+            ),
+        ],
+      ),
+    );
+  }
+
+  static String _payloadTypeLabel(int payloadType) {
+    switch (payloadType) {
+      case 0x00:
+        return 'REQ';
+      case 0x01:
+        return 'RESP';
+      case 0x02:
+        return 'TXT';
+      case 0x03:
+        return 'ACK';
+      case 0x04:
+        return 'ADVERT';
+      case 0x05:
+        return 'GRP_TXT';
+      case 0x06:
+        return 'GRP_DATA';
+      case 0x07:
+        return 'ANON_REQ';
+      case 0x08:
+        return 'PATH';
+      case 0x09:
+        return 'TRACE';
+      case 0x0A:
+        return 'MULTIPART';
+      case 0x0B:
+        return 'CONTROL';
+      default:
+        return '0x${payloadType.toRadixString(16).padLeft(2, '0')}';
+    }
+  }
+
+  static String _nodeLabel(ResolvedNodeHash node) {
+    if (node.isOwnNode) {
+      return '${node.label} (${node.hexLabel})';
+    }
+    if (node.matchCount == 0) {
+      return node.hexLabel;
+    }
+    if (node.isUniqueMatch) {
+      return '${node.label} (${node.hexLabel})';
+    }
+    return '${node.label} (${node.hexLabel}, ${node.matchCount} matches)';
+  }
+}
+
+class _RouteHopChip extends StatelessWidget {
+  final int index;
+  final ResolvedNodeHash node;
+
+  const _RouteHopChip({required this.index, required this.node});
+
+  @override
+  Widget build(BuildContext context) {
+    final color = node.isOwnNode
+        ? Colors.blue
+        : node.isUniqueMatch
+        ? Colors.green
+        : Colors.orange;
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 8),
+      decoration: BoxDecoration(
+        color: color.withValues(alpha: 0.12),
+        borderRadius: BorderRadius.circular(999),
+        border: Border.all(color: color.withValues(alpha: 0.35)),
+      ),
+      child: Text(
+        '$index. ${_RouteSection._nodeLabel(node)}',
+        style: const TextStyle(fontSize: 12, fontWeight: FontWeight.w600),
+      ),
+    );
+  }
+}
+
 class _FactCard extends StatelessWidget {
   final IconData icon;
   final String label;

lib/screens/repeaters_map_screen.dart

@@ -0,0 +1,775 @@
+import 'dart:typed_data';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_map/flutter_map.dart' as flutter_map;
+import 'package:geolocator/geolocator.dart';
+import 'package:latlong2/latlong.dart';
+import 'package:provider/provider.dart';
+
+import '../models/contact.dart';
+import '../providers/connection_provider.dart';
+import '../providers/contacts_provider.dart';
+import '../services/mesh_map_nodes_service.dart';
+
+class RepeatersMapScreen extends StatefulWidget {
+  const RepeatersMapScreen({super.key});
+
+  @override
+  State<RepeatersMapScreen> createState() => _RepeatersMapScreenState();
+}
+
+class _RepeatersMapScreenState extends State<RepeatersMapScreen> {
+  static const LatLng _fallbackCenter = LatLng(46.0569, 14.5058);
+  static const double _fallbackZoom = 7;
+  static const double _myLocationZoom = 14;
+
+  final flutter_map.MapController _mapController = flutter_map.MapController();
+
+  List<MeshMapNode> _onlineRepeaters = const [];
+  bool _isLoading = true;
+  bool _didFitCamera = false;
+  String? _error;
+  double _currentZoom = _fallbackZoom;
+  LatLng? _myLocation;
+  final Set<String> _addingRepeaters = <String>{};
+
+  @override
+  void initState() {
+    super.initState();
+    _loadRepeaters();
+  }
+
+  Future<void> _loadRepeaters({bool forceRefresh = false}) async {
+    setState(() {
+      _isLoading = true;
+      _error = null;
+      if (forceRefresh) {
+        _didFitCamera = false;
+      }
+    });
+
+    try {
+      final nodes = await MeshMapNodesService.fetchNodes(
+        forceRefresh: forceRefresh,
+      );
+      final repeaters = nodes.where(MeshMapNodesService.isRepeater).toList();
+
+      if (!mounted) return;
+      setState(() {
+        _onlineRepeaters = repeaters;
+        _isLoading = false;
+      });
+      _refreshMyLocation();
+    } catch (error) {
+      final cached = await MeshMapNodesService.loadCachedNodes();
+      final repeaters = cached.where(MeshMapNodesService.isRepeater).toList();
+
+      if (!mounted) return;
+      setState(() {
+        _onlineRepeaters = repeaters;
+        _isLoading = false;
+        _error = repeaters.isEmpty
+            ? 'Unable to load repeaters right now.'
+            : 'Showing cached repeaters. Pull to retry.';
+      });
+      _refreshMyLocation();
+    }
+  }
+
+  List<_MapRepeater> _mergeRepeaters({
+    required List<MeshMapNode> onlineNodes,
+    required List<Contact> contactRepeaters,
+  }) {
+    final merged = <String, _MapRepeater>{};
+
+    for (final node in onlineNodes) {
+      merged[node.publicKey] = _MapRepeater(
+        publicKey: node.publicKey,
+        name: node.name,
+        latitude: node.latitude,
+        longitude: node.longitude,
+        isFromContacts: false,
+        isFromOnline: true,
+      );
+    }
+
+    for (final contact in contactRepeaters) {
+      final location = contact.displayLocation;
+      if (location == null) {
+        continue;
+      }
+
+      final key = contact.publicKeyHex.toLowerCase();
+      final existing = merged[key];
+      merged[key] = _MapRepeater(
+        publicKey: key,
+        name: contact.displayName.isNotEmpty
+            ? contact.displayName
+            : existing?.name ?? 'Unknown repeater',
+        latitude: existing?.latitude ?? location.latitude,
+        longitude: existing?.longitude ?? location.longitude,
+        isFromContacts: true,
+        isFromOnline: existing?.isFromOnline ?? false,
+      );
+    }
+
+    final repeaters = merged.values.toList()
+      ..sort((a, b) => a.name.toLowerCase().compareTo(b.name.toLowerCase()));
+    return repeaters;
+  }
+
+  Future<void> _refreshMyLocation() async {
+    try {
+      final position = await Geolocator.getCurrentPosition(
+        locationSettings: const LocationSettings(
+          accuracy: LocationAccuracy.best,
+          distanceFilter: 0,
+        ),
+      );
+      if (!mounted) return;
+      setState(() {
+        _myLocation = LatLng(position.latitude, position.longitude);
+      });
+    } catch (_) {
+      // Best effort only.
+    }
+  }
+
+  void _fitCameraIfNeeded(List<_MapRepeater> repeaters) {
+    if (_didFitCamera || repeaters.isEmpty || !mounted) {
+      return;
+    }
+
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (!mounted || _didFitCamera || repeaters.isEmpty) {
+        return;
+      }
+
+      if (repeaters.length == 1) {
+        final repeater = repeaters.first;
+        _mapController.move(LatLng(repeater.latitude, repeater.longitude), 13);
+        _currentZoom = 13;
+      } else {
+        final bounds = flutter_map.LatLngBounds.fromPoints(
+          repeaters
+              .map((node) => LatLng(node.latitude, node.longitude))
+              .toList(),
+        );
+        _mapController.fitCamera(
+          flutter_map.CameraFit.bounds(
+            bounds: bounds,
+            padding: const EdgeInsets.all(48),
+          ),
+        );
+      }
+
+      _didFitCamera = true;
+    });
+  }
+
+  void _showRepeaterDetails(_MapRepeater repeater) {
+    final isAdding = _addingRepeaters.contains(repeater.publicKey);
+    final canAdd = !repeater.isFromContacts;
+    final isConnected = context
+        .read<ConnectionProvider>()
+        .deviceInfo
+        .isConnected;
+
+    showModalBottomSheet<void>(
+      context: context,
+      showDragHandle: true,
+      builder: (context) => SafeArea(
+        child: Padding(
+          padding: const EdgeInsets.fromLTRB(20, 0, 20, 24),
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              Text(
+                repeater.name,
+                style: Theme.of(
+                  context,
+                ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.w700),
+              ),
+              const SizedBox(height: 12),
+              _InfoLine(
+                label: 'Public key',
+                value: repeater.publicKey,
+                monospace: true,
+              ),
+              _InfoLine(
+                label: 'Coordinates',
+                value:
+                    '${repeater.latitude.toStringAsFixed(5)}, ${repeater.longitude.toStringAsFixed(5)}',
+              ),
+              _InfoLine(label: 'Source', value: repeater.sourceLabel),
+              const SizedBox(height: 12),
+              if (canAdd)
+                SizedBox(
+                  width: double.infinity,
+                  child: FilledButton.icon(
+                    onPressed: !isConnected || isAdding
+                        ? null
+                        : () async {
+                            Navigator.of(context).pop();
+                            await _addRepeaterToContacts(repeater);
+                          },
+                    icon: isAdding
+                        ? const SizedBox(
+                            width: 16,
+                            height: 16,
+                            child: CircularProgressIndicator(strokeWidth: 2),
+                          )
+                        : const Icon(Icons.person_add_alt_1),
+                    label: Text(
+                      !isConnected
+                          ? 'Connect device to add'
+                          : 'Add to contacts',
+                    ),
+                  ),
+                )
+              else
+                SizedBox(
+                  width: double.infinity,
+                  child: FilledButton.icon(
+                    onPressed: null,
+                    icon: const Icon(Icons.check_circle),
+                    label: const Text('Already in contacts'),
+                  ),
+                ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Future<void> _addRepeaterToContacts(_MapRepeater repeater) async {
+    if (_addingRepeaters.contains(repeater.publicKey)) {
+      return;
+    }
+
+    final connectionProvider = context.read<ConnectionProvider>();
+    if (!connectionProvider.deviceInfo.isConnected) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(
+          content: Text('Connect to a device before adding contacts'),
+        ),
+      );
+      return;
+    }
+
+    setState(() {
+      _addingRepeaters.add(repeater.publicKey);
+    });
+
+    try {
+      await connectionProvider.getContact(_hexToBytes(repeater.publicKey));
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text('${repeater.name} added to contacts')),
+      );
+    } catch (error) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text('Failed to add ${repeater.name}: $error')),
+      );
+    } finally {
+      if (mounted) {
+        setState(() {
+          _addingRepeaters.remove(repeater.publicKey);
+        });
+      }
+    }
+  }
+
+  Uint8List _hexToBytes(String hex) {
+    final normalized = hex.replaceAll(':', '').trim().toLowerCase();
+    return Uint8List.fromList(
+      List<int>.generate(
+        normalized.length ~/ 2,
+        (index) => int.parse(
+          normalized.substring(index * 2, index * 2 + 2),
+          radix: 16,
+        ),
+      ),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final contactsProvider = context.watch<ContactsProvider>();
+    final repeaters = _mergeRepeaters(
+      onlineNodes: _onlineRepeaters,
+      contactRepeaters: contactsProvider.repeaters,
+    );
+    _fitCameraIfNeeded(repeaters);
+    final clusters = _buildClusters(repeaters);
+    final markers = clusters.map((cluster) {
+      final markerColor = switch (cluster.status) {
+        _ClusterStatus.contactsOnly => const Color(0xFF7C3AED),
+        _ClusterStatus.onlineOnly => const Color(0xFFE8681D),
+        _ClusterStatus.both => const Color(0xFF1B8F4F),
+        _ClusterStatus.mixed => const Color(0xFF2563EB),
+      };
+
+      if (cluster.members.length == 1) {
+        final repeater = cluster.members.first;
+        return flutter_map.Marker(
+          point: cluster.center,
+          width: 80,
+          height: 100,
+          child: GestureDetector(
+            onTap: () => _showRepeaterDetails(repeater),
+            child: _RepeaterMarker(color: markerColor, label: repeater.name),
+          ),
+        );
+      }
+
+      return flutter_map.Marker(
+        point: cluster.center,
+        width: 48,
+        height: 48,
+        child: GestureDetector(
+          onTap: () => _zoomToCluster(cluster),
+          child: _ClusterMarker(
+            color: markerColor,
+            count: cluster.members.length,
+          ),
+        ),
+      );
+    }).toList();
+    final allMarkers = <flutter_map.Marker>[
+      ...markers,
+      if (_myLocation != null)
+        flutter_map.Marker(
+          point: _myLocation!,
+          width: 24,
+          height: 24,
+          child: Container(
+            decoration: BoxDecoration(
+              color: const Color(0xFF2563EB),
+              shape: BoxShape.circle,
+              border: Border.all(color: Colors.white, width: 3),
+              boxShadow: [
+                BoxShadow(
+                  color: Colors.black.withValues(alpha: 0.18),
+                  blurRadius: 12,
+                  offset: const Offset(0, 4),
+                ),
+              ],
+            ),
+          ),
+        ),
+    ];
+
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Repeaters Map'),
+        actions: [
+          IconButton(
+            onPressed: _isLoading
+                ? null
+                : () => _loadRepeaters(forceRefresh: true),
+            icon: const Icon(Icons.refresh),
+            tooltip: 'Refresh',
+          ),
+        ],
+      ),
+      body: Stack(
+        children: [
+          flutter_map.FlutterMap(
+            mapController: _mapController,
+            options: flutter_map.MapOptions(
+              initialCenter: _fallbackCenter,
+              initialZoom: _fallbackZoom,
+              onPositionChanged: (camera, hasGesture) {
+                final nextZoom = camera.zoom;
+                if (nextZoom != _currentZoom && mounted) {
+                  setState(() {
+                    _currentZoom = nextZoom;
+                  });
+                }
+              },
+            ),
+            children: [
+              flutter_map.TileLayer(
+                urlTemplate: 'https://tile.openstreetmap.org/{z}/{x}/{y}.png',
+                userAgentPackageName: 'app.meshcore.sar',
+              ),
+              flutter_map.MarkerLayer(markers: allMarkers),
+            ],
+          ),
+          if (_error != null)
+            Positioned(
+              top: 16,
+              left: 16,
+              right: 16,
+              child: Material(
+                elevation: 2,
+                borderRadius: BorderRadius.circular(14),
+                color: Theme.of(context).colorScheme.surface,
+                child: Padding(
+                  padding: const EdgeInsets.symmetric(
+                    horizontal: 16,
+                    vertical: 12,
+                  ),
+                  child: Text(_error!),
+                ),
+              ),
+            ),
+          if (_isLoading) const Center(child: CircularProgressIndicator()),
+          if (!_isLoading && repeaters.isEmpty)
+            Center(
+              child: Padding(
+                padding: const EdgeInsets.all(24),
+                child: Text(
+                  _error ?? 'No repeaters available.',
+                  textAlign: TextAlign.center,
+                ),
+              ),
+            ),
+          if (repeaters.isNotEmpty)
+            Positioned(
+              left: 16,
+              top: _error == null ? 16 : 72,
+              child: Material(
+                elevation: 2,
+                borderRadius: BorderRadius.circular(14),
+                color: Theme.of(context).colorScheme.surface,
+                child: Padding(
+                  padding: const EdgeInsets.symmetric(
+                    horizontal: 14,
+                    vertical: 10,
+                  ),
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    mainAxisSize: MainAxisSize.min,
+                    children: const [
+                      _LegendRow(
+                        color: Color(0xFF7C3AED),
+                        label: 'From contacts',
+                      ),
+                      SizedBox(height: 8),
+                      _LegendRow(
+                        color: Color(0xFFE8681D),
+                        label: 'Online only',
+                      ),
+                      SizedBox(height: 8),
+                      _LegendRow(color: Color(0xFF1B8F4F), label: 'In both'),
+                    ],
+                  ),
+                ),
+              ),
+            ),
+          if (repeaters.isNotEmpty)
+            Positioned(
+              left: 16,
+              right: 16,
+              bottom: 16,
+              child: Material(
+                elevation: 3,
+                borderRadius: BorderRadius.circular(16),
+                color: Theme.of(context).colorScheme.surface,
+                child: Padding(
+                  padding: const EdgeInsets.symmetric(
+                    horizontal: 16,
+                    vertical: 12,
+                  ),
+                  child: Text(
+                    '${repeaters.length} repeaters',
+                    style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                      fontWeight: FontWeight.w700,
+                    ),
+                  ),
+                ),
+              ),
+            ),
+        ],
+      ),
+      floatingActionButton: FloatingActionButton(
+        onPressed: _jumpToMyLocation,
+        tooltip: 'My location',
+        child: const Icon(Icons.my_location),
+      ),
+    );
+  }
+
+  Future<void> _jumpToMyLocation() async {
+    await _refreshMyLocation();
+    final myLocation = _myLocation;
+    if (!mounted || myLocation == null) {
+      return;
+    }
+
+    _mapController.move(myLocation, _myLocationZoom);
+    setState(() {
+      _currentZoom = _myLocationZoom;
+    });
+  }
+
+  List<_RepeaterCluster> _buildClusters(List<_MapRepeater> repeaters) {
+    if (repeaters.isEmpty) {
+      return const [];
+    }
+
+    if (_currentZoom >= 11.5) {
+      return repeaters
+          .map(
+            (repeater) => _RepeaterCluster(
+              members: [repeater],
+              center: LatLng(repeater.latitude, repeater.longitude),
+              status: repeater.clusterStatus,
+            ),
+          )
+          .toList();
+    }
+
+    final cellSize = _gridSizeForZoom(_currentZoom);
+    final buckets = <String, List<_MapRepeater>>{};
+
+    for (final repeater in repeaters) {
+      final latBucket = (repeater.latitude / cellSize).floor();
+      final lonBucket = (repeater.longitude / cellSize).floor();
+      final key = '$latBucket:$lonBucket';
+      buckets.putIfAbsent(key, () => <_MapRepeater>[]).add(repeater);
+    }
+
+    return buckets.values.map((members) {
+      final centerLat =
+          members.map((node) => node.latitude).reduce((a, b) => a + b) /
+          members.length;
+      final centerLon =
+          members.map((node) => node.longitude).reduce((a, b) => a + b) /
+          members.length;
+      final statuses = members.map((node) => node.clusterStatus).toSet();
+      return _RepeaterCluster(
+        members: members,
+        center: LatLng(centerLat, centerLon),
+        status: statuses.length == 1 ? statuses.first : _ClusterStatus.mixed,
+      );
+    }).toList();
+  }
+
+  double _gridSizeForZoom(double zoom) {
+    if (zoom < 5) return 3.0;
+    if (zoom < 7) return 1.5;
+    if (zoom < 9) return 0.7;
+    if (zoom < 10.5) return 0.28;
+    return 0.12;
+  }
+
+  void _zoomToCluster(_RepeaterCluster cluster) {
+    if (cluster.members.isEmpty) {
+      return;
+    }
+
+    final bounds = flutter_map.LatLngBounds.fromPoints(
+      cluster.members
+          .map((node) => LatLng(node.latitude, node.longitude))
+          .toList(),
+    );
+    _mapController.fitCamera(
+      flutter_map.CameraFit.bounds(
+        bounds: bounds,
+        padding: const EdgeInsets.all(64),
+        maxZoom: (_currentZoom + 2).clamp(8, 14),
+      ),
+    );
+  }
+}
+
+class _InfoLine extends StatelessWidget {
+  final String label;
+  final String value;
+  final bool monospace;
+
+  const _InfoLine({
+    required this.label,
+    required this.value,
+    this.monospace = false,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.only(bottom: 8),
+      child: Row(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          SizedBox(
+            width: 92,
+            child: Text(
+              label,
+              style: Theme.of(
+                context,
+              ).textTheme.bodyMedium?.copyWith(fontWeight: FontWeight.w600),
+            ),
+          ),
+          Expanded(
+            child: Text(
+              value,
+              style: monospace
+                  ? const TextStyle(fontFamily: 'monospace')
+                  : null,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class _LegendRow extends StatelessWidget {
+  final Color color;
+  final String label;
+
+  const _LegendRow({required this.color, required this.label});
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        Container(
+          width: 12,
+          height: 12,
+          decoration: BoxDecoration(color: color, shape: BoxShape.circle),
+        ),
+        const SizedBox(width: 8),
+        Text(label),
+      ],
+    );
+  }
+}
+
+class _RepeaterMarker extends StatelessWidget {
+  final Color color;
+  final String label;
+
+  const _RepeaterMarker({required this.color, required this.label});
+
+  @override
+  Widget build(BuildContext context) {
+    return Column(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        Container(
+          decoration: BoxDecoration(
+            color: color,
+            shape: BoxShape.circle,
+            border: Border.all(color: Colors.white, width: 2),
+            boxShadow: [
+              BoxShadow(
+                color: Colors.black.withValues(alpha: 0.3),
+                blurRadius: 4,
+                offset: const Offset(0, 2),
+              ),
+            ],
+          ),
+          padding: const EdgeInsets.all(6),
+          child: const Icon(Icons.router, color: Colors.white, size: 18),
+        ),
+        const SizedBox(height: 2),
+        Container(
+          constraints: const BoxConstraints(maxWidth: 80),
+          padding: const EdgeInsets.symmetric(horizontal: 4, vertical: 1),
+          decoration: BoxDecoration(
+            color: Colors.black.withValues(alpha: 0.7),
+            borderRadius: BorderRadius.circular(3),
+          ),
+          child: Text(
+            label,
+            style: const TextStyle(
+              color: Colors.white,
+              fontSize: 9,
+              fontWeight: FontWeight.bold,
+            ),
+            overflow: TextOverflow.ellipsis,
+            maxLines: 1,
+            textAlign: TextAlign.center,
+          ),
+        ),
+      ],
+    );
+  }
+}
+
+class _ClusterMarker extends StatelessWidget {
+  final Color color;
+  final int count;
+
+  const _ClusterMarker({required this.color, required this.count});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      decoration: BoxDecoration(
+        color: color,
+        shape: BoxShape.circle,
+        border: Border.all(color: Colors.white, width: 2),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withValues(alpha: 0.22),
+            blurRadius: 10,
+            offset: const Offset(0, 3),
+          ),
+        ],
+      ),
+      alignment: Alignment.center,
+      child: Text(
+        '$count',
+        style: const TextStyle(
+          color: Colors.white,
+          fontWeight: FontWeight.w800,
+          fontSize: 14,
+        ),
+      ),
+    );
+  }
+}
+
+enum _ClusterStatus { contactsOnly, onlineOnly, both, mixed }
+
+class _RepeaterCluster {
+  final List<_MapRepeater> members;
+  final LatLng center;
+  final _ClusterStatus status;
+
+  const _RepeaterCluster({
+    required this.members,
+    required this.center,
+    required this.status,
+  });
+}
+
+class _MapRepeater {
+  final String publicKey;
+  final String name;
+  final double latitude;
+  final double longitude;
+  final bool isFromContacts;
+  final bool isFromOnline;
+
+  const _MapRepeater({
+    required this.publicKey,
+    required this.name,
+    required this.latitude,
+    required this.longitude,
+    required this.isFromContacts,
+    required this.isFromOnline,
+  });
+
+  String get sourceLabel {
+    if (isFromContacts && isFromOnline) return 'Contacts and online';
+    if (isFromContacts) return 'Contacts';
+    return 'Online';
+  }
+
+  _ClusterStatus get clusterStatus {
+    if (isFromContacts && isFromOnline) return _ClusterStatus.both;
+    if (isFromContacts) return _ClusterStatus.contactsOnly;
+    return _ClusterStatus.onlineOnly;
+  }
+}

lib/screens/spectrum_scan_screen.dart

@@ -0,0 +1,601 @@
+import 'package:flutter/material.dart';
+import 'package:meshcore_client/meshcore_client.dart';
+import 'package:provider/provider.dart';
+import '../models/device_info.dart';
+import '../providers/connection_provider.dart';
+import '../widgets/device/spectrum_scan_panel.dart';
+
+class SpectrumScanScreen extends StatefulWidget {
+  const SpectrumScanScreen({super.key});
+
+  @override
+  State<SpectrumScanScreen> createState() => _SpectrumScanScreenState();
+}
+
+class _SpectrumScanScreenState extends State<SpectrumScanScreen> {
+  static const List<String> _bandwidthOptions = [
+    '7.8 kHz',
+    '10.4 kHz',
+    '15.6 kHz',
+    '20.8 kHz',
+    '31.25 kHz',
+    '41.7 kHz',
+    '62.5 kHz',
+    '125 kHz',
+    '250 kHz',
+    '500 kHz',
+  ];
+
+  String _selectedBandwidth = '62.5 kHz';
+  bool _isSpectrumScanRunning = false;
+  bool _rangeInitialized = false;
+  String? _lastRangeSourceKey;
+  late double _scanRangeMinMhz;
+  late double _scanRangeMaxMhz;
+  late RangeValues _scanRangeValues;
+  List<SpectrumScanCandidate> _scanCandidates = const [];
+  int? _selectedScanFrequencyKhz;
+  int _completedScanSectors = 0;
+  int _totalScanSectors = 0;
+
+  List<SpectrumScanCandidate> get _recommendedScanCandidates =>
+      _scanCandidates.take(8).toList();
+
+  @override
+  void initState() {
+    super.initState();
+    final deviceInfo = _deviceInfo;
+    if (deviceInfo.radioBw != null &&
+        deviceInfo.radioBw! >= 0 &&
+        deviceInfo.radioBw! < _bandwidthOptions.length) {
+      _selectedBandwidth = _bandwidthOptions[deviceInfo.radioBw!];
+    }
+    _syncRangeFromDevice(deviceInfo);
+    _selectedScanFrequencyKhz = deviceInfo.radioFreq;
+  }
+
+  DeviceInfo get _deviceInfo => context.read<ConnectionProvider>().deviceInfo;
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    _syncRangeFromDevice(context.watch<ConnectionProvider>().deviceInfo);
+  }
+
+  void _syncRangeFromDevice(DeviceInfo deviceInfo) {
+    final minKhz = deviceInfo.spectrumScanMinKhz;
+    final maxKhz = deviceInfo.spectrumScanMaxKhz;
+    late double normalizedMinMhz;
+    late double normalizedMaxMhz;
+    late String sourceKey;
+
+    if (minKhz != null && maxKhz != null && maxKhz > minKhz) {
+      final normalized = _normalizeScanRange(
+        minKhz / 1000.0,
+        maxKhz / 1000.0,
+        deviceInfo.radioFreq != null ? deviceInfo.radioFreq! / 1000.0 : null,
+      );
+      normalizedMinMhz = normalized.$1;
+      normalizedMaxMhz = normalized.$2;
+      sourceKey = 'fw:$minKhz:$maxKhz';
+    } else {
+      final normalized = _normalizeScanRange(
+        null,
+        null,
+        deviceInfo.radioFreq != null ? deviceInfo.radioFreq! / 1000.0 : null,
+      );
+      normalizedMinMhz = normalized.$1;
+      normalizedMaxMhz = normalized.$2;
+      sourceKey =
+          'fallback:${deviceInfo.radioFreq != null ? deviceInfo.radioFreq! ~/ 1000 : 869525}';
+    }
+
+    if (_rangeInitialized && _lastRangeSourceKey == sourceKey) {
+      return;
+    }
+
+    _scanRangeMinMhz = normalizedMinMhz;
+    _scanRangeMaxMhz = normalizedMaxMhz;
+
+    if (_scanRangeMaxMhz <= _scanRangeMinMhz) {
+      _scanRangeMaxMhz = _scanRangeMinMhz + 0.5;
+    }
+
+    _scanRangeValues = RangeValues(_scanRangeMinMhz, _scanRangeMaxMhz);
+    _rangeInitialized = true;
+    _lastRangeSourceKey = sourceKey;
+  }
+
+  (double, double) _normalizeScanRange(
+    double? minMhz,
+    double? maxMhz,
+    double? centerMhz,
+  ) {
+    const hardMinMhz = 800.0;
+    const hardMaxMhz = 950.0;
+    final center = centerMhz ?? 869.525;
+
+    if (minMhz != null && maxMhz != null) {
+      final clampedMin = minMhz.clamp(hardMinMhz, hardMaxMhz);
+      final clampedMax = maxMhz.clamp(hardMinMhz, hardMaxMhz);
+      if (clampedMax > clampedMin) {
+        return (clampedMin, clampedMax);
+      }
+    }
+
+    if (center >= 900.0 && center <= 930.0) {
+      return (902.0, 928.0);
+    }
+
+    return (863.0, 870.0);
+  }
+
+  double _bandwidthToKhz(String bw) {
+    switch (bw) {
+      case '7.8 kHz':
+        return 7.8;
+      case '10.4 kHz':
+        return 10.4;
+      case '15.6 kHz':
+        return 15.6;
+      case '20.8 kHz':
+        return 20.8;
+      case '31.25 kHz':
+        return 31.25;
+      case '41.7 kHz':
+        return 41.7;
+      case '62.5 kHz':
+        return 62.5;
+      case '125 kHz':
+        return 125.0;
+      case '250 kHz':
+        return 250.0;
+      case '500 kHz':
+        return 500.0;
+      default:
+        return 62.5;
+    }
+  }
+
+  String _currentParamProfile(DeviceInfo deviceInfo) {
+    final sf = deviceInfo.radioSf ?? 8;
+    final cr = deviceInfo.radioCr ?? 8;
+    return 'BW $_selectedBandwidth  |  SF$sf  |  CR 4/$cr';
+  }
+
+  String _recommendationTitle(int index) {
+    switch (index) {
+      case 0:
+        return 'Best candidate';
+      case 1:
+        return 'Alternate';
+      case 2:
+        return 'Fallback';
+      default:
+        return 'Candidate ${index + 1}';
+    }
+  }
+
+  List<int> _possibleBracketFrequenciesKhz() {
+    final bandwidthKhz = _bandwidthToKhz(_selectedBandwidth);
+    final halfBandwidthKhz = bandwidthKhz / 2.0;
+    final startKhz = (_scanRangeValues.start * 1000).round();
+    final stopKhz = (_scanRangeValues.end * 1000).round();
+    final firstCenterKhz = (startKhz + halfBandwidthKhz).round();
+    final lastCenterKhz = (stopKhz - halfBandwidthKhz).round();
+
+    if (lastCenterKhz < firstCenterKhz) {
+      return const [];
+    }
+
+    final stepKhz = bandwidthKhz >= 125.0 ? bandwidthKhz.round() : 25;
+    final centers = <int>[];
+    for (
+      var centerKhz = firstCenterKhz;
+      centerKhz <= lastCenterKhz && centers.length < 8;
+      centerKhz += stepKhz
+    ) {
+      centers.add(centerKhz);
+    }
+
+    if (centers.isEmpty || centers.last != lastCenterKhz) {
+      centers.add(lastCenterKhz);
+    }
+
+    return centers.toSet().toList()..sort();
+  }
+
+  void _resetDerivedScanResults() {
+    _scanCandidates = const [];
+    _selectedScanFrequencyKhz = null;
+  }
+
+  List<(int startKhz, int stopKhz)> _buildScanSectors(double bandwidthKhz) {
+    final startKhz = (_scanRangeValues.start * 1000).round();
+    final stopKhz = (_scanRangeValues.end * 1000).round();
+    final sectorWidthKhz = (bandwidthKhz * 24).round().clamp(250, 1200);
+    final overlapKhz = bandwidthKhz.round().clamp(8, 500);
+    final sectors = <(int startKhz, int stopKhz)>[];
+
+    var sectorStartKhz = startKhz;
+    while (sectorStartKhz < stopKhz) {
+      final sectorStopKhz = (sectorStartKhz + sectorWidthKhz).clamp(
+        sectorStartKhz + overlapKhz,
+        stopKhz,
+      );
+      sectors.add((sectorStartKhz, sectorStopKhz));
+      if (sectorStopKhz >= stopKhz) {
+        break;
+      }
+      sectorStartKhz = sectorStopKhz - overlapKhz;
+    }
+
+    return sectors;
+  }
+
+  List<SpectrumScanCandidate> _mergeSectorCandidates(
+    Iterable<SpectrumScanCandidate> candidates,
+  ) {
+    final byFrequency = <int, SpectrumScanCandidate>{};
+    for (final candidate in candidates) {
+      final existing = byFrequency[candidate.centerFrequencyKhz];
+      if (existing == null ||
+          candidate.occupancyPercent < existing.occupancyPercent ||
+          (candidate.occupancyPercent == existing.occupancyPercent &&
+              candidate.peakRssiDbm < existing.peakRssiDbm) ||
+          (candidate.occupancyPercent == existing.occupancyPercent &&
+              candidate.peakRssiDbm == existing.peakRssiDbm &&
+              candidate.avgRssiDbm < existing.avgRssiDbm)) {
+        byFrequency[candidate.centerFrequencyKhz] = candidate;
+      }
+    }
+
+    final merged = byFrequency.values.toList()
+      ..sort((a, b) {
+        final occupancyCompare = a.occupancyPercent.compareTo(
+          b.occupancyPercent,
+        );
+        if (occupancyCompare != 0) return occupancyCompare;
+        final peakCompare = a.peakRssiDbm.compareTo(b.peakRssiDbm);
+        if (peakCompare != 0) return peakCompare;
+        return a.avgRssiDbm.compareTo(b.avgRssiDbm);
+      });
+    return merged;
+  }
+
+  Future<void> _runSpectrumScan() async {
+    final connectionProvider = context.read<ConnectionProvider>();
+    final bandwidthKhz = _bandwidthToKhz(_selectedBandwidth);
+    final sectors = _buildScanSectors(bandwidthKhz);
+    final sectorCandidates = <SpectrumScanCandidate>[];
+
+    setState(() {
+      _isSpectrumScanRunning = true;
+      _resetDerivedScanResults();
+      _completedScanSectors = 0;
+      _totalScanSectors = sectors.length;
+    });
+
+    try {
+      for (var i = 0; i < sectors.length; i++) {
+        final sector = sectors[i];
+        final result = await connectionProvider.scanSpectrum(
+          startFrequencyKhz: sector.$1,
+          stopFrequencyKhz: sector.$2,
+          bandwidthKhz: bandwidthKhz.round(),
+          stepKhz: (bandwidthKhz / 2).round().clamp(1, 1000),
+          dwellMs: 160,
+          thresholdDb: 8,
+        );
+        if (result != null) {
+          sectorCandidates.addAll(result.candidates);
+          final mergedCandidates = _mergeSectorCandidates(sectorCandidates);
+          if (mounted) {
+            setState(() {
+              _scanCandidates = mergedCandidates;
+              if (_selectedScanFrequencyKhz == null &&
+                  mergedCandidates.isNotEmpty) {
+                _selectedScanFrequencyKhz =
+                    mergedCandidates.first.centerFrequencyKhz;
+              }
+              _completedScanSectors = i + 1;
+            });
+          }
+        } else if (mounted) {
+          setState(() {
+            _completedScanSectors = i + 1;
+          });
+        }
+      }
+    } finally {
+      if (mounted) {
+        setState(() {
+          _isSpectrumScanRunning = false;
+          if (_completedScanSectors == 0) {
+            _totalScanSectors = sectors.length;
+          }
+        });
+      }
+    }
+
+    if (!mounted) return;
+
+    final mergedCandidates = _mergeSectorCandidates(sectorCandidates);
+    if (mergedCandidates.isEmpty) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(
+          content: Text('Spectrum scan returned no candidate frequencies'),
+          backgroundColor: Colors.red,
+        ),
+      );
+      return;
+    }
+
+    setState(() {
+      _scanCandidates = mergedCandidates;
+      _selectedScanFrequencyKhz = mergedCandidates.first.centerFrequencyKhz;
+    });
+  }
+
+  Future<void> _applySelectedScanFrequency() async {
+    if (_selectedScanFrequencyKhz == null) return;
+
+    final connectionProvider = context.read<ConnectionProvider>();
+    final deviceInfo = connectionProvider.deviceInfo;
+
+    await connectionProvider.setRadioParams(
+      frequency: _selectedScanFrequencyKhz!,
+      bandwidth: _bandwidthOptions.indexOf(_selectedBandwidth),
+      spreadingFactor: deviceInfo.radioSf ?? 8,
+      codingRate: deviceInfo.radioCr ?? 8,
+      repeat: deviceInfo.clientRepeat,
+    );
+    await connectionProvider.refreshDeviceInfo();
+
+    if (!mounted) return;
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Text(
+          'Applied ${(_selectedScanFrequencyKhz! / 1000.0).toStringAsFixed(3)} MHz',
+        ),
+        backgroundColor: Colors.green,
+      ),
+    );
+  }
+
+  int? _currentPreviewFrequencyKhz(DeviceInfo deviceInfo) {
+    if (_selectedScanFrequencyKhz != null) {
+      return _selectedScanFrequencyKhz;
+    }
+    return deviceInfo.radioFreq;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final deviceInfo = context.watch<ConnectionProvider>().deviceInfo;
+    final theme = Theme.of(context);
+    final possibleBracketFrequencies = _possibleBracketFrequenciesKhz();
+    final recommendedScanCandidates = _recommendedScanCandidates;
+    final recommendationFrequencies = recommendedScanCandidates.isNotEmpty
+        ? recommendedScanCandidates
+              .map((candidate) => candidate.centerFrequencyKhz)
+              .toList()
+        : possibleBracketFrequencies;
+
+    return Scaffold(
+      appBar: AppBar(title: const Text('Spectrum Scan')),
+      body: ListView(
+        padding: const EdgeInsets.all(16),
+        children: [
+          Card(
+            child: Padding(
+              padding: const EdgeInsets.all(16),
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  DropdownButtonFormField<String>(
+                    initialValue: _selectedBandwidth,
+                    decoration: const InputDecoration(
+                      labelText: 'Bandwidth',
+                      border: OutlineInputBorder(),
+                      helperText:
+                          'Scan and apply frequencies for this bandwidth',
+                    ),
+                    items: _bandwidthOptions.map((value) {
+                      return DropdownMenuItem<String>(
+                        value: value,
+                        child: Text(value),
+                      );
+                    }).toList(),
+                    onChanged: (value) {
+                      if (value == null) return;
+                      setState(() {
+                        _selectedBandwidth = value;
+                        _resetDerivedScanResults();
+                      });
+                    },
+                  ),
+                  const SizedBox(height: 16),
+                  Text(
+                    deviceInfo.spectrumScanMinKhz != null &&
+                            deviceInfo.spectrumScanMaxKhz != null
+                        ? 'Firmware scan range: ${_scanRangeMinMhz.toStringAsFixed(3)}-${_scanRangeMaxMhz.toStringAsFixed(3)} MHz'
+                        : 'Fallback scan range selected from current band. MeshCore commonly uses EU868 or US915.',
+                    style: theme.textTheme.bodySmall?.copyWith(
+                      color: theme.colorScheme.onSurfaceVariant,
+                    ),
+                  ),
+                  if (_isSpectrumScanRunning) ...[
+                    const SizedBox(height: 8),
+                    Text(
+                      'Scanning sector ${_completedScanSectors + 1} of $_totalScanSectors. Results update as each sector completes.',
+                      style: theme.textTheme.bodySmall?.copyWith(
+                        color: theme.colorScheme.primary,
+                        fontWeight: FontWeight.w600,
+                      ),
+                    ),
+                  ],
+                  const SizedBox(height: 12),
+                  SpectrumScanPanel(
+                    theme: theme,
+                    scanSupported: deviceInfo.supportsSpectrumScan == true,
+                    isRunning: _isSpectrumScanRunning,
+                    rangeMinMhz: _scanRangeMinMhz,
+                    rangeMaxMhz: _scanRangeMaxMhz,
+                    rangeValues: _scanRangeValues,
+                    bandwidthKhz: _bandwidthToKhz(_selectedBandwidth),
+                    selectedFrequencyKhz: _currentPreviewFrequencyKhz(
+                      deviceInfo,
+                    ),
+                    graphCandidates: _scanCandidates,
+                    selectableCandidates: recommendedScanCandidates,
+                    onRangeChanged: (values) {
+                      setState(() {
+                        _scanRangeValues = values;
+                        _resetDerivedScanResults();
+                      });
+                    },
+                    onCandidateChanged: (value) {
+                      setState(() {
+                        _selectedScanFrequencyKhz = value;
+                      });
+                    },
+                    onRunScan: _runSpectrumScan,
+                    onApplySelected: _applySelectedScanFrequency,
+                  ),
+                  if (recommendationFrequencies.isNotEmpty) ...[
+                    const SizedBox(height: 18),
+                    Text(
+                      _scanCandidates.isNotEmpty
+                          ? 'Recommended profiles'
+                          : 'Possible brackets',
+                      style: theme.textTheme.titleMedium?.copyWith(
+                        fontWeight: FontWeight.w700,
+                      ),
+                    ),
+                    const SizedBox(height: 8),
+                    Text(
+                      _scanCandidates.isNotEmpty
+                          ? 'Suggested frequencies from the latest scan with the radio parameters to keep alongside them.'
+                          : 'Usable frequency brackets derived from the selected span and bandwidth, even without live scan data.',
+                      style: theme.textTheme.bodySmall?.copyWith(
+                        color: theme.colorScheme.onSurfaceVariant,
+                      ),
+                    ),
+                    const SizedBox(height: 12),
+                    for (
+                      var i = 0;
+                      i < recommendationFrequencies.length;
+                      i++
+                    ) ...[
+                      _RecommendationTile(
+                        title: _recommendationTitle(i),
+                        frequencyKhz: recommendationFrequencies[i],
+                        candidate: recommendedScanCandidates.isNotEmpty
+                            ? recommendedScanCandidates[i]
+                            : null,
+                        bandwidthKhz: _bandwidthToKhz(_selectedBandwidth),
+                        paramsLabel: _currentParamProfile(deviceInfo),
+                        isSelected:
+                            _selectedScanFrequencyKhz ==
+                            recommendationFrequencies[i],
+                        onSelect: () {
+                          setState(() {
+                            _selectedScanFrequencyKhz =
+                                recommendationFrequencies[i];
+                          });
+                        },
+                      ),
+                      if (i != recommendationFrequencies.length - 1)
+                        const SizedBox(height: 10),
+                    ],
+                  ],
+                ],
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class _RecommendationTile extends StatelessWidget {
+  final String title;
+  final int frequencyKhz;
+  final SpectrumScanCandidate? candidate;
+  final double bandwidthKhz;
+  final String paramsLabel;
+  final bool isSelected;
+  final VoidCallback onSelect;
+
+  const _RecommendationTile({
+    required this.title,
+    required this.frequencyKhz,
+    required this.candidate,
+    required this.bandwidthKhz,
+    required this.paramsLabel,
+    required this.isSelected,
+    required this.onSelect,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final scheme = theme.colorScheme;
+
+    return InkWell(
+      onTap: onSelect,
+      borderRadius: BorderRadius.circular(14),
+      child: Container(
+        padding: const EdgeInsets.all(14),
+        decoration: BoxDecoration(
+          color: isSelected
+              ? scheme.primaryContainer.withValues(alpha: 0.55)
+              : scheme.surfaceContainerHighest.withValues(alpha: 0.35),
+          borderRadius: BorderRadius.circular(14),
+          border: Border.all(
+            color: isSelected ? scheme.primary : scheme.outlineVariant,
+          ),
+        ),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Row(
+              children: [
+                Expanded(
+                  child: Text(
+                    title,
+                    style: theme.textTheme.titleSmall?.copyWith(
+                      fontWeight: FontWeight.w700,
+                    ),
+                  ),
+                ),
+                if (isSelected)
+                  Icon(Icons.check_circle, color: scheme.primary, size: 18),
+              ],
+            ),
+            const SizedBox(height: 8),
+            Text(
+              '${(frequencyKhz / 1000.0).toStringAsFixed(3)} MHz',
+              style: theme.textTheme.headlineSmall?.copyWith(
+                fontWeight: FontWeight.w800,
+              ),
+            ),
+            const SizedBox(height: 6),
+            Text(paramsLabel, style: theme.textTheme.bodyMedium),
+            const SizedBox(height: 6),
+            Text(
+              candidate != null
+                  ? 'Occupancy ${candidate!.occupancyPercent}%  |  Avg ${candidate!.avgRssiDbm} dBm  |  Peak ${candidate!.peakRssiDbm} dBm'
+                  : 'Bracket ${(frequencyKhz / 1000.0 - bandwidthKhz / 2000.0).toStringAsFixed(3)}-${(frequencyKhz / 1000.0 + bandwidthKhz / 2000.0).toStringAsFixed(3)} MHz',
+              style: theme.textTheme.bodySmall?.copyWith(
+                color: scheme.onSurfaceVariant,
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/screens/welcome_wizard_screen.dart

@@ -1,6 +1,9 @@
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 import '../l10n/app_localizations.dart';
+import '../providers/connection_provider.dart';
 import '../services/wizard_preferences.dart';
+import '../widgets/connection_dialog.dart';
 
 /// Welcome wizard screen to introduce new users to the app
 class WelcomeWizardScreen extends StatefulWidget {
@@ -14,12 +17,171 @@ class WelcomeWizardScreen extends StatefulWidget {
 
 class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
   final PageController _pageController = PageController();
+  final TextEditingController _deviceNameController = TextEditingController();
   int _currentPage = 0;
+  bool _isApplyingDeviceSetup = false;
   static const int _totalPages = 6;
+  static const List<_RadioPreset> _radioPresets = [
+    // Official MeshCore config presets from https://api.meshcore.nz/api/v1/config
+    _RadioPreset(
+      id: 'australia',
+      label: 'Australia',
+      summary: '915.800 MHz, BW 250 kHz, SF10, CR5',
+      frequencyKhz: 915800,
+      bandwidth: 8,
+      spreadingFactor: 10,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'australia_narrow',
+      label: 'Australia (Narrow)',
+      summary: '916.575 MHz, BW 62.5 kHz, SF7, CR8',
+      frequencyKhz: 916575,
+      bandwidth: 6,
+      spreadingFactor: 7,
+      codingRate: 8,
+    ),
+    _RadioPreset(
+      id: 'australia_sa_wa',
+      label: 'Australia: SA, WA',
+      summary: '923.125 MHz, BW 62.5 kHz, SF8, CR8',
+      frequencyKhz: 923125,
+      bandwidth: 6,
+      spreadingFactor: 8,
+      codingRate: 8,
+    ),
+    _RadioPreset(
+      id: 'australia_qld',
+      label: 'Australia: QLD',
+      summary: '923.125 MHz, BW 62.5 kHz, SF8, CR5',
+      frequencyKhz: 923125,
+      bandwidth: 6,
+      spreadingFactor: 8,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'eu_uk_narrow',
+      label: 'EU/UK (Narrow)',
+      summary: '869.618 MHz, BW 62.5 kHz, SF8, CR8',
+      frequencyKhz: 869618,
+      bandwidth: 6,
+      spreadingFactor: 8,
+      codingRate: 8,
+    ),
+    _RadioPreset(
+      id: 'eu_uk_deprecated',
+      label: 'EU/UK (Deprecated)',
+      summary: '869.525 MHz, BW 250 kHz, SF11, CR5',
+      frequencyKhz: 869525,
+      bandwidth: 8,
+      spreadingFactor: 11,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'czech_republic_narrow',
+      label: 'Czech Republic (Narrow)',
+      summary: '869.432 MHz, BW 62.5 kHz, SF7, CR5',
+      frequencyKhz: 869432,
+      bandwidth: 6,
+      spreadingFactor: 7,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'eu_433_long_range',
+      label: 'EU 433MHz (Long Range)',
+      summary: '433.650 MHz, BW 250 kHz, SF11, CR5',
+      frequencyKhz: 433650,
+      bandwidth: 8,
+      spreadingFactor: 11,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'new_zealand',
+      label: 'New Zealand',
+      summary: '917.375 MHz, BW 250 kHz, SF11, CR5',
+      frequencyKhz: 917375,
+      bandwidth: 8,
+      spreadingFactor: 11,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'new_zealand_narrow',
+      label: 'New Zealand (Narrow)',
+      summary: '917.375 MHz, BW 62.5 kHz, SF7, CR5',
+      frequencyKhz: 917375,
+      bandwidth: 6,
+      spreadingFactor: 7,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'portugal_433',
+      label: 'Portugal 433',
+      summary: '433.375 MHz, BW 62.5 kHz, SF9, CR6',
+      frequencyKhz: 433375,
+      bandwidth: 6,
+      spreadingFactor: 9,
+      codingRate: 6,
+    ),
+    _RadioPreset(
+      id: 'portugal_868',
+      label: 'Portugal 868',
+      summary: '869.618 MHz, BW 62.5 kHz, SF7, CR6',
+      frequencyKhz: 869618,
+      bandwidth: 6,
+      spreadingFactor: 7,
+      codingRate: 6,
+    ),
+    _RadioPreset(
+      id: 'switzerland',
+      label: 'Switzerland',
+      summary: '869.618 MHz, BW 62.5 kHz, SF8, CR8',
+      frequencyKhz: 869618,
+      bandwidth: 6,
+      spreadingFactor: 8,
+      codingRate: 8,
+    ),
+    _RadioPreset(
+      id: 'usa_canada_recommended',
+      label: 'USA/Canada (Recommended)',
+      summary: '910.525 MHz, BW 62.5 kHz, SF7, CR5',
+      frequencyKhz: 910525,
+      bandwidth: 6,
+      spreadingFactor: 7,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'vietnam_narrow',
+      label: 'Vietnam (Narrow)',
+      summary: '920.250 MHz, BW 62.5 kHz, SF8, CR5',
+      frequencyKhz: 920250,
+      bandwidth: 6,
+      spreadingFactor: 8,
+      codingRate: 5,
+    ),
+    _RadioPreset(
+      id: 'vietnam_deprecated',
+      label: 'Vietnam (Deprecated)',
+      summary: '920.250 MHz, BW 250 kHz, SF11, CR5',
+      frequencyKhz: 920250,
+      bandwidth: 8,
+      spreadingFactor: 11,
+      codingRate: 5,
+    ),
+  ];
+  _RadioPreset _selectedPreset = _radioPresets[4];
+
+  @override
+  void initState() {
+    super.initState();
+    final deviceInfo = context.read<ConnectionProvider>().deviceInfo;
+    _deviceNameController.text =
+        deviceInfo.selfName ?? deviceInfo.deviceName ?? '';
+  }
 
   @override
   void dispose() {
     _pageController.dispose();
+    _deviceNameController.dispose();
     super.dispose();
   }
 
@@ -30,7 +192,9 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
   }
 
   void _nextPage() {
-    if (_currentPage < _totalPages - 1) {
+    if (_currentPage == 1) {
+      _handleDeviceSetupAction();
+    } else if (_currentPage < _totalPages - 1) {
       _pageController.nextPage(
         duration: const Duration(milliseconds: 300),
         curve: Curves.easeInOut,
@@ -56,6 +220,98 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
     }
   }
 
+  Future<void> _openConnectionDialog() async {
+    await showModalBottomSheet(
+      context: context,
+      isScrollControlled: true,
+      builder: (context) => const ConnectionDialog(),
+    );
+    if (!mounted) return;
+    final connectionProvider = context.read<ConnectionProvider>();
+    if (connectionProvider.deviceInfo.isConnected) {
+      await connectionProvider.refreshDeviceInfo();
+    }
+    if (!mounted) return;
+    final deviceInfo = connectionProvider.deviceInfo;
+    final fetchedName = deviceInfo.selfName ?? deviceInfo.deviceName ?? '';
+    if (fetchedName.isNotEmpty) {
+      setState(() {
+        _deviceNameController.text = fetchedName;
+      });
+    } else {
+      setState(() {});
+    }
+  }
+
+  Future<void> _handleDeviceSetupAction() async {
+    final l10n = AppLocalizations.of(context)!;
+    final connectionProvider = context.read<ConnectionProvider>();
+    final deviceInfo = connectionProvider.deviceInfo;
+    if (!deviceInfo.isConnected) {
+      await _openConnectionDialog();
+      return;
+    }
+
+    final trimmedName = _deviceNameController.text.trim();
+    if (trimmedName.isEmpty) {
+      ScaffoldMessenger.of(
+        context,
+      ).showSnackBar(SnackBar(content: Text(l10n.wizardEnterDeviceName)));
+      return;
+    }
+
+    setState(() {
+      _isApplyingDeviceSetup = true;
+    });
+
+    try {
+      await connectionProvider.setAdvertName(trimmedName);
+      await connectionProvider.setRadioParams(
+        frequency: _selectedPreset.frequencyKhz,
+        bandwidth: _selectedPreset.bandwidth,
+        spreadingFactor: _selectedPreset.spreadingFactor,
+        codingRate: _selectedPreset.codingRate,
+      );
+      await connectionProvider.refreshDeviceInfo();
+
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(
+            l10n.wizardDeviceSetupSaved(trimmedName, _selectedPreset.label),
+          ),
+          backgroundColor: Colors.green,
+        ),
+      );
+      _pageController.nextPage(
+        duration: const Duration(milliseconds: 300),
+        curve: Curves.easeInOut,
+      );
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(l10n.failedToSave(e.toString())),
+          backgroundColor: Colors.red,
+        ),
+      );
+    } finally {
+      if (mounted) {
+        setState(() {
+          _isApplyingDeviceSetup = false;
+        });
+      }
+    }
+  }
+
+  void _skipDeviceSetupStep() {
+    if (_isApplyingDeviceSetup) return;
+    _pageController.nextPage(
+      duration: const Duration(milliseconds: 300),
+      curve: Curves.easeInOut,
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     final l10n = AppLocalizations.of(context)!;
@@ -68,7 +324,7 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
           children: [
             // Top bar with skip button
             Padding(
-              padding: const EdgeInsets.all(16.0),
+              padding: const EdgeInsets.fromLTRB(16, 12, 16, 8),
               child: Row(
                 mainAxisAlignment: MainAxisAlignment.spaceBetween,
                 children: [
@@ -96,10 +352,11 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
               child: PageView(
                 controller: _pageController,
                 onPageChanged: _onPageChanged,
+                physics: const NeverScrollableScrollPhysics(),
                 children: [
                   _buildWelcomePage(context, l10n, colorScheme),
+                  _buildConnectDevicePage(context, l10n, colorScheme),
                   _buildConnectingPage(context, l10n, colorScheme),
-                  _buildSimpleModePage(context, l10n, colorScheme),
                   _buildChannelPage(context, l10n, colorScheme),
                   _buildContactsPage(context, l10n, colorScheme),
                   _buildMapPage(context, l10n, colorScheme),
@@ -109,7 +366,7 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
 
             // Page indicators
             Padding(
-              padding: const EdgeInsets.all(16.0),
+              padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
               child: Row(
                 mainAxisAlignment: MainAxisAlignment.center,
                 children: List.generate(
@@ -131,11 +388,11 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
 
             // Next/Get Started button
             Padding(
-              padding: const EdgeInsets.all(16.0),
+              padding: const EdgeInsets.fromLTRB(16, 8, 16, 16),
               child: SizedBox(
                 width: double.infinity,
                 child: ElevatedButton(
-                  onPressed: _nextPage,
+                  onPressed: _isApplyingDeviceSetup ? null : _nextPage,
                   style: ElevatedButton.styleFrom(
                     padding: const EdgeInsets.symmetric(vertical: 16.0),
                     shape: RoundedRectangleBorder(
@@ -143,7 +400,9 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
                     ),
                   ),
                   child: Text(
-                    _currentPage < _totalPages - 1
+                    _currentPage == 1
+                        ? _deviceSetupButtonLabel(context)
+                        : _currentPage < _totalPages - 1
                         ? l10n.wizardNext
                         : l10n.wizardGetStarted,
                     style: const TextStyle(fontSize: 16),
@@ -166,7 +425,21 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
       icon: Icons.waving_hand,
       iconColor: Colors.orange,
       title: l10n.wizardWelcomeTitle,
-      description: l10n.wizardWelcomeDescription,
+      description: l10n.wizardOverviewDescription,
+      features: [
+        _FeatureItem(
+          icon: Icons.chat_bubble_outline,
+          text: l10n.wizardOverviewFeature1,
+        ),
+        _FeatureItem(
+          icon: Icons.emergency_share,
+          text: l10n.wizardOverviewFeature2,
+        ),
+        _FeatureItem(
+          icon: Icons.settings_input_antenna,
+          text: l10n.wizardOverviewFeature3,
+        ),
+      ],
       colorScheme: colorScheme,
     );
   }
@@ -177,75 +450,225 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
     ColorScheme colorScheme,
   ) {
     return _buildPage(
-      icon: Icons.bluetooth_searching,
+      icon: Icons.forum_rounded,
       iconColor: Colors.blue,
-      title: l10n.wizardConnectingTitle,
-      description: l10n.wizardConnectingDescription,
+      title: l10n.wizardMessagingTitle,
+      description: l10n.wizardMessagingDescription,
       features: [
-        _FeatureItem(
-          icon: Icons.radio,
-          text: l10n.wizardConnectingFeature1,
-        ),
-        _FeatureItem(
-          icon: Icons.link,
-          text: l10n.wizardConnectingFeature2,
-        ),
-        _FeatureItem(
-          icon: Icons.wifi_off,
-          text: l10n.wizardConnectingFeature3,
-        ),
+        _FeatureItem(icon: Icons.chat, text: l10n.wizardMessagingFeature1),
+        _FeatureItem(icon: Icons.campaign, text: l10n.wizardMessagingFeature2),
+        _FeatureItem(icon: Icons.mic, text: l10n.wizardMessagingFeature3),
       ],
       colorScheme: colorScheme,
     );
   }
 
-  Widget _buildSimpleModePage(
+  Widget _buildConnectDevicePage(
     BuildContext context,
     AppLocalizations l10n,
     ColorScheme colorScheme,
   ) {
-    return _buildPage(
-      icon: Icons.toggle_on,
-      iconColor: Colors.green,
-      title: l10n.wizardSimpleModeTitle,
-      description: l10n.wizardSimpleModeDescription,
-      features: [
-        _FeatureItem(
-          icon: Icons.check_circle_outline,
-          text: l10n.wizardSimpleModeFeature1,
+    final connectionProvider = context.watch<ConnectionProvider>();
+    final deviceInfo = connectionProvider.deviceInfo;
+    final isConnected = deviceInfo.isConnected;
+    final connectedName = deviceInfo.selfName ?? deviceInfo.deviceName;
+
+    return LayoutBuilder(
+      builder: (context, constraints) => Center(
+        child: ConstrainedBox(
+          constraints: BoxConstraints(
+            maxWidth: 600,
+            maxHeight: constraints.maxHeight,
+          ),
+          child: Padding(
+            padding: const EdgeInsets.fromLTRB(20, 12, 20, 12),
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.stretch,
+              children: [
+                _buildPageHeader(
+                  context: context,
+                  colorScheme: colorScheme,
+                  icon: Icons.bluetooth_connected,
+                  iconColor: Colors.green,
+                  title: l10n.wizardConnectDeviceTitle,
+                  description: l10n.wizardConnectDeviceDescription,
+                  badge: l10n.wizardSetupBadge,
+                ),
+                const SizedBox(height: 16),
+                _buildContentCard(
+                  colorScheme: colorScheme,
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.stretch,
+                    children: [
+                      Row(
+                        children: [
+                          Icon(
+                            isConnected
+                                ? Icons.check_circle
+                                : Icons.bluetooth_searching,
+                            color: isConnected
+                                ? colorScheme.primary
+                                : colorScheme.onSurfaceVariant,
+                          ),
+                          const SizedBox(width: 12),
+                          Expanded(
+                            child: Text(
+                              isConnected
+                                  ? l10n.wizardConnectedToDevice(
+                                      connectedName ?? l10n.device,
+                                    )
+                                  : l10n.wizardNoDeviceConnected,
+                              style: Theme.of(context).textTheme.bodyMedium
+                                  ?.copyWith(fontWeight: FontWeight.w600),
+                            ),
+                          ),
+                          TextButton(
+                            onPressed: _openConnectionDialog,
+                            child: Text(
+                              isConnected ? l10n.change : l10n.connect,
+                            ),
+                          ),
+                        ],
+                      ),
+                      Align(
+                        alignment: Alignment.centerRight,
+                        child: TextButton(
+                          onPressed: _skipDeviceSetupStep,
+                          child: Text(l10n.wizardSkipForNow),
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+                const SizedBox(height: 12),
+                _buildContentCard(
+                  colorScheme: colorScheme,
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.stretch,
+                    children: [
+                      TextField(
+                        controller: _deviceNameController,
+                        textInputAction: TextInputAction.done,
+                        decoration: InputDecoration(
+                          labelText: l10n.wizardDeviceNameLabel,
+                          border: OutlineInputBorder(),
+                          helperText: l10n.wizardDeviceNameHelp,
+                        ),
+                      ),
+                      const SizedBox(height: 12),
+                      DropdownButtonFormField<_RadioPreset>(
+                        initialValue: _selectedPreset,
+                        isExpanded: true,
+                        decoration: InputDecoration(
+                          labelText: l10n.wizardConfigRegionLabel,
+                          border: OutlineInputBorder(),
+                          helperText: l10n.wizardConfigRegionHelp,
+                        ),
+                        items: _radioPresets
+                            .map(
+                              (preset) => DropdownMenuItem<_RadioPreset>(
+                                value: preset,
+                                child: Text(
+                                  preset.label,
+                                  overflow: TextOverflow.ellipsis,
+                                ),
+                              ),
+                            )
+                            .toList(),
+                        onChanged: (preset) {
+                          if (preset == null) return;
+                          setState(() {
+                            _selectedPreset = preset;
+                          });
+                        },
+                      ),
+                    ],
+                  ),
+                ),
+                const SizedBox(height: 16),
+                _buildContentCard(
+                  colorScheme: colorScheme,
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Text(
+                        _selectedPreset.label,
+                        style: Theme.of(context).textTheme.titleMedium
+                            ?.copyWith(fontWeight: FontWeight.w700),
+                      ),
+                      const SizedBox(height: 4),
+                      Text(
+                        _selectedPreset.summary,
+                        style: Theme.of(context).textTheme.bodyMedium,
+                      ),
+                      const SizedBox(height: 14),
+                      ...[
+                        _FeatureItem(
+                          icon: Icons.rule,
+                          text: l10n.wizardPresetNote1,
+                        ),
+                        _FeatureItem(
+                          icon: Icons.settings_input_antenna,
+                          text: l10n.wizardPresetNote2,
+                        ),
+                        _FeatureItem(
+                          icon: Icons.public,
+                          text: l10n.wizardPresetNote3,
+                        ),
+                      ].map(
+                        (feature) => Padding(
+                          padding: const EdgeInsets.symmetric(vertical: 5),
+                          child: _buildFeatureRow(
+                            context,
+                            colorScheme,
+                            feature,
+                            iconSize: 20,
+                            gap: 12,
+                          ),
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+              ],
+            ),
+          ),
         ),
-        _FeatureItem(
-          icon: Icons.settings,
-          text: l10n.wizardSimpleModeFeature2,
-        ),
-      ],
-      colorScheme: colorScheme,
+      ),
     );
   }
 
+  String _deviceSetupButtonLabel(BuildContext context) {
+    final isConnected = context
+        .watch<ConnectionProvider>()
+        .deviceInfo
+        .isConnected;
+    if (_isApplyingDeviceSetup) {
+      return AppLocalizations.of(context)!.wizardSaving;
+    }
+    final l10n = AppLocalizations.of(context)!;
+    return isConnected
+        ? l10n.wizardSaveAndContinue
+        : l10n.wizardConnectDeviceTitle;
+  }
+
   Widget _buildChannelPage(
     BuildContext context,
     AppLocalizations l10n,
     ColorScheme colorScheme,
   ) {
     return _buildPage(
-      icon: Icons.campaign,
+      icon: Icons.groups_rounded,
       iconColor: Colors.purple,
-      title: l10n.wizardChannelTitle,
-      description: l10n.wizardChannelDescription,
+      title: l10n.wizardNetworkTitle,
+      description: l10n.wizardNetworkDescription,
       features: [
         _FeatureItem(
-          icon: Icons.public,
-          text: l10n.wizardChannelFeature1,
-        ),
-        _FeatureItem(
-          icon: Icons.groups,
-          text: l10n.wizardChannelFeature2,
-        ),
-        _FeatureItem(
-          icon: Icons.send,
-          text: l10n.wizardChannelFeature3,
+          icon: Icons.person_add_alt_1,
+          text: l10n.wizardNetworkFeature1,
         ),
+        _FeatureItem(icon: Icons.route, text: l10n.wizardNetworkFeature2),
+        _FeatureItem(icon: Icons.hub, text: l10n.wizardNetworkFeature3),
       ],
       colorScheme: colorScheme,
     );
@@ -257,23 +680,14 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
     ColorScheme colorScheme,
   ) {
     return _buildPage(
-      icon: Icons.people,
+      icon: Icons.map_rounded,
       iconColor: Colors.teal,
-      title: l10n.wizardContactsTitle,
-      description: l10n.wizardContactsDescription,
+      title: l10n.wizardMapOpsTitle,
+      description: l10n.wizardMapOpsDescription,
       features: [
-        _FeatureItem(
-          icon: Icons.person_add,
-          text: l10n.wizardContactsFeature1,
-        ),
-        _FeatureItem(
-          icon: Icons.chat,
-          text: l10n.wizardContactsFeature2,
-        ),
-        _FeatureItem(
-          icon: Icons.battery_std,
-          text: l10n.wizardContactsFeature3,
-        ),
+        _FeatureItem(icon: Icons.location_on, text: l10n.wizardMapOpsFeature1),
+        _FeatureItem(icon: Icons.draw, text: l10n.wizardMapOpsFeature2),
+        _FeatureItem(icon: Icons.router, text: l10n.wizardMapOpsFeature3),
       ],
       colorScheme: colorScheme,
     );
@@ -285,26 +699,16 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
     ColorScheme colorScheme,
   ) {
     return _buildPage(
-      icon: Icons.map,
+      icon: Icons.tune_rounded,
       iconColor: Colors.red,
-      title: l10n.wizardMapTitle,
-      description: l10n.wizardMapDescription,
+      title: l10n.wizardToolsTitle,
+      description: l10n.wizardToolsDescription,
       features: [
+        _FeatureItem(icon: Icons.settings, text: l10n.wizardToolsFeature1),
+        _FeatureItem(icon: Icons.sensors, text: l10n.wizardToolsFeature2),
         _FeatureItem(
-          icon: Icons.location_on,
-          text: l10n.wizardMapFeature1,
-        ),
-        _FeatureItem(
-          icon: Icons.person_pin_circle,
-          text: l10n.wizardMapFeature2,
-        ),
-        _FeatureItem(
-          icon: Icons.offline_pin,
-          text: l10n.wizardMapFeature3,
-        ),
-        _FeatureItem(
-          icon: Icons.draw,
-          text: l10n.wizardMapFeature4,
+          icon: Icons.analytics_outlined,
+          text: l10n.wizardToolsFeature3,
         ),
       ],
       colorScheme: colorScheme,
@@ -319,76 +723,149 @@ class _WelcomeWizardScreenState extends State<WelcomeWizardScreen> {
     List<_FeatureItem>? features,
     required ColorScheme colorScheme,
   }) {
-    return SingleChildScrollView(
-      padding: const EdgeInsets.all(24.0),
-      child: Column(
-        mainAxisAlignment: MainAxisAlignment.center,
-        children: [
-          const SizedBox(height: 20),
-          // Icon
-          Container(
-            padding: const EdgeInsets.all(24.0),
-            decoration: BoxDecoration(
-              color: iconColor.withValues(alpha: 0.1),
-              shape: BoxShape.circle,
-            ),
-            child: Icon(
-              icon,
-              size: 80,
-              color: iconColor,
-            ),
+    final l10n = AppLocalizations.of(context)!;
+    return LayoutBuilder(
+      builder: (context, constraints) => Center(
+        child: ConstrainedBox(
+          constraints: BoxConstraints(
+            maxWidth: 560,
+            maxHeight: constraints.maxHeight,
           ),
-          const SizedBox(height: 32),
-          // Title
-          Text(
-            title,
-            style: Theme.of(context).textTheme.headlineMedium?.copyWith(
-                  fontWeight: FontWeight.bold,
-                  color: colorScheme.onSurface,
+          child: Padding(
+            padding: const EdgeInsets.fromLTRB(20, 12, 20, 12),
+            child: Column(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                _buildPageHeader(
+                  context: context,
+                  colorScheme: colorScheme,
+                  icon: icon,
+                  iconColor: iconColor,
+                  title: title,
+                  description: description,
+                  badge: l10n.wizardOverviewBadge,
                 ),
-            textAlign: TextAlign.center,
-          ),
-          const SizedBox(height: 16),
-          // Description
-          Text(
-            description,
-            style: Theme.of(context).textTheme.bodyLarge?.copyWith(
-                  color: colorScheme.onSurface.withValues(alpha: 0.7),
-                  height: 1.5,
-                ),
-            textAlign: TextAlign.center,
-          ),
-          if (features != null && features.isNotEmpty) ...[
-            const SizedBox(height: 32),
-            // Features list
-            ...features.map((feature) => Padding(
-                  padding: const EdgeInsets.symmetric(vertical: 8.0),
-                  child: Row(
-                    children: [
-                      Icon(
-                        feature.icon,
-                        color: colorScheme.primary,
-                        size: 24,
-                      ),
-                      const SizedBox(width: 16),
-                      Expanded(
-                        child: Text(
-                          feature.text,
-                          style:
-                              Theme.of(context).textTheme.bodyMedium?.copyWith(
-                                    color: colorScheme.onSurface,
-                                  ),
-                        ),
-                      ),
-                    ],
+                if (features != null && features.isNotEmpty) ...[
+                  const SizedBox(height: 18),
+                  _buildContentCard(
+                    colorScheme: colorScheme,
+                    child: Column(
+                      children: features
+                          .map(
+                            (feature) => Padding(
+                              padding: const EdgeInsets.symmetric(vertical: 7),
+                              child: _buildFeatureRow(
+                                context,
+                                colorScheme,
+                                feature,
+                              ),
+                            ),
+                          )
+                          .toList(),
+                    ),
                   ),
-                )),
-          ],
-          const SizedBox(height: 20),
-        ],
+                ],
+              ],
+            ),
+          ),
+        ),
       ),
     );
   }
+
+  Widget _buildPageHeader({
+    required BuildContext context,
+    required ColorScheme colorScheme,
+    required IconData icon,
+    required Color iconColor,
+    required String title,
+    required String description,
+    required String badge,
+  }) {
+    return Column(
+      children: [
+        Container(
+          padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
+          decoration: BoxDecoration(
+            color: colorScheme.secondaryContainer,
+            borderRadius: BorderRadius.circular(999),
+          ),
+          child: Text(
+            badge,
+            style: Theme.of(context).textTheme.labelLarge?.copyWith(
+              color: colorScheme.onSecondaryContainer,
+              fontWeight: FontWeight.w700,
+            ),
+          ),
+        ),
+        const SizedBox(height: 12),
+        Container(
+          padding: const EdgeInsets.all(18),
+          decoration: BoxDecoration(
+            color: iconColor.withValues(alpha: 0.1),
+            shape: BoxShape.circle,
+          ),
+          child: Icon(icon, size: 56, color: iconColor),
+        ),
+        const SizedBox(height: 18),
+        Text(
+          title,
+          style: Theme.of(context).textTheme.headlineSmall?.copyWith(
+            fontWeight: FontWeight.bold,
+            color: colorScheme.onSurface,
+          ),
+          textAlign: TextAlign.center,
+        ),
+        const SizedBox(height: 10),
+        Text(
+          description,
+          style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+            color: colorScheme.onSurface.withValues(alpha: 0.72),
+            height: 1.4,
+          ),
+          textAlign: TextAlign.center,
+        ),
+      ],
+    );
+  }
+
+  Widget _buildContentCard({
+    required ColorScheme colorScheme,
+    required Widget child,
+  }) {
+    return Container(
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: colorScheme.surfaceContainerHighest,
+        borderRadius: BorderRadius.circular(18),
+      ),
+      child: child,
+    );
+  }
+
+  Widget _buildFeatureRow(
+    BuildContext context,
+    ColorScheme colorScheme,
+    _FeatureItem feature, {
+    double iconSize = 22,
+    double gap = 14,
+  }) {
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Icon(feature.icon, color: colorScheme.primary, size: iconSize),
+        SizedBox(width: gap),
+        Expanded(
+          child: Text(
+            feature.text,
+            style: Theme.of(
+              context,
+            ).textTheme.bodyMedium?.copyWith(color: colorScheme.onSurface),
+          ),
+        ),
+      ],
+    );
+  }
 }
 
 class _FeatureItem {
@@ -397,3 +874,23 @@ class _FeatureItem {
 
   _FeatureItem({required this.icon, required this.text});
 }
+
+class _RadioPreset {
+  final String id;
+  final String label;
+  final String summary;
+  final int frequencyKhz;
+  final int bandwidth;
+  final int spreadingFactor;
+  final int codingRate;
+
+  const _RadioPreset({
+    required this.id,
+    required this.label,
+    required this.summary,
+    required this.frequencyKhz,
+    required this.bandwidth,
+    required this.spreadingFactor,
+    required this.codingRate,
+  });
+}

lib/services/background_location_service.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:io';
 import 'package:flutter/widgets.dart';
 import 'package:geolocator/geolocator.dart';
 import 'package:shared_preferences/shared_preferences.dart';
@@ -58,6 +59,16 @@ class BackgroundLocationService {
       return false;
     }
 
+    if (Platform.isIOS && permission != LocationPermission.always) {
+      permission = await Geolocator.requestPermission();
+      if (permission != LocationPermission.always) {
+        debugPrint(
+          '⚠️ [BackgroundLocation] iOS background tracking requires Always permission',
+        );
+        return false;
+      }
+    }
+
     // Save settings
     final prefs = await SharedPreferences.getInstance();
     await prefs.setBool(_prefKeyEnabled, true);
@@ -68,8 +79,7 @@ class BackgroundLocationService {
     try {
       _positionSubscription =
           Geolocator.getPositionStream(
-            locationSettings: LocationSettings(
-              accuracy: LocationAccuracy.best,
+            locationSettings: _buildLocationSettings(
               distanceFilter: distanceThreshold.toInt(),
             ),
           ).listen((Position position) async {
@@ -171,4 +181,22 @@ class BackgroundLocationService {
       await startTracking(distanceThreshold: distance);
     }
   }
+
+  LocationSettings _buildLocationSettings({int distanceFilter = 10}) {
+    if (Platform.isIOS) {
+      return AppleSettings(
+        accuracy: LocationAccuracy.best,
+        activityType: ActivityType.fitness,
+        allowBackgroundLocationUpdates: true,
+        distanceFilter: distanceFilter,
+        pauseLocationUpdatesAutomatically: false,
+        showBackgroundLocationIndicator: true,
+      );
+    }
+
+    return LocationSettings(
+      accuracy: LocationAccuracy.best,
+      distanceFilter: distanceFilter,
+    );
+  }
 }

lib/services/build_info_service.dart

@@ -1,6 +1,5 @@
-import 'dart:io' show Platform;
+import 'package:flutter/foundation.dart' show TargetPlatform, defaultTargetPlatform, debugPrint, kIsWeb;
 import 'package:flutter/services.dart';
-import 'package:flutter/foundation.dart';
 
 /// Service for accessing build information from native platform code
 /// Currently supports Android only - returns "unknown" for other platforms
@@ -25,7 +24,7 @@ class BuildInfoService {
     }
 
     // Only Android has the platform channel implementation
-    if (!Platform.isAndroid) {
+    if (kIsWeb || defaultTargetPlatform != TargetPlatform.android) {
       debugPrint('[BuildInfoService] Not on Android platform, returning "unknown"');
       _cachedCommitHash = 'unknown';
       return _cachedCommitHash!;

lib/services/cayenne_lpp_parser.dart

@@ -25,6 +25,14 @@ class CayenneLppParser {
 
     int fieldCount = 0;
     while (reader.hasRemaining) {
+      if (fieldCount > 0 && _isZeroPaddedTail(data, reader.remainingBytesCount)) {
+        debugPrint(
+          '    Detected zero-padded telemetry tail, stopping parse at position '
+          '${data.length - reader.remainingBytesCount}',
+        );
+        break;
+      }
+
       try {
         fieldCount++;
         debugPrint(
@@ -250,6 +258,14 @@ class CayenneLppParser {
     return ((voltage - 3.0) / 1.2) * 100.0;
   }
 
+  static bool _isZeroPaddedTail(Uint8List data, int remainingBytes) {
+    final start = data.length - remainingBytes;
+    for (int i = start; i < data.length; i++) {
+      if (data[i] != 0) return false;
+    }
+    return remainingBytes > 0;
+  }
+
   /// Create Cayenne LPP data for GPS location
   /// Standard Cayenne LPP GPS format (type 0x88):
   /// - Latitude: 3 bytes, signed 24-bit, big-endian, × 10000

lib/services/developer_mode_service.dart

@@ -0,0 +1,15 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+class DeveloperModeService {
+  static const String _developerModeKey = 'developer_mode_enabled';
+
+  static Future<bool> isEnabled() async {
+    final prefs = await SharedPreferences.getInstance();
+    return prefs.getBool(_developerModeKey) ?? false;
+  }
+
+  static Future<void> setEnabled(bool enabled) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setBool(_developerModeKey, enabled);
+  }
+}

lib/services/locale_preferences.dart

@@ -15,6 +15,12 @@ class LocalePreferences {
     Locale('fr'), // French
     Locale('it'), // Italian
     Locale('el'), // Greek
+    Locale('pt'), // Portuguese
+    Locale('tr'), // Turkish
+    Locale('pl'), // Polish
+    Locale('uk'), // Ukrainian
+    Locale('ru'), // Russian
+    Locale('zh'), // Chinese
   ];
 
   /// Get the saved locale or return null to use system locale
@@ -64,6 +70,18 @@ class LocalePreferences {
         return 'Italiano';
       case 'el':
         return 'Greek';
+      case 'pt':
+        return 'Portuguese';
+      case 'tr':
+        return 'Turkish';
+      case 'pl':
+        return 'Polish';
+      case 'uk':
+        return 'Ukrainian';
+      case 'ru':
+        return 'Русский';
+      case 'zh':
+        return '简体中文';
       default:
         return locale.languageCode;
     }
@@ -88,6 +106,18 @@ class LocalePreferences {
         return 'Italiano';
       case 'el':
         return 'Ελληνικά';
+      case 'pt':
+        return 'Português';
+      case 'tr':
+        return 'Türkçe';
+      case 'pl':
+        return 'Polski';
+      case 'uk':
+        return 'Українська';
+      case 'ru':
+        return 'Русский';
+      case 'zh':
+        return '简体中文';
       default:
         return locale.languageCode;
     }

lib/services/location_tracking_service.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:io';
 import 'package:flutter/foundation.dart';
 import 'package:geolocator/geolocator.dart';
 import 'package:shared_preferences/shared_preferences.dart';
@@ -41,6 +42,12 @@ class LocationTrackingService {
   static const String _prefKeyGpsUpdateDistance = 'map_gps_update_distance';
   static const String _prefKeyLastLat = 'background_last_lat';
   static const String _prefKeyLastLon = 'background_last_lon';
+  static const String _prefKeyFastLocationEnabled =
+      'fast_location_updates_enabled';
+  static const String _prefKeyFastMovementThreshold =
+      'fast_location_movement_threshold_meters';
+  static const String _prefKeyFastActiveCadence =
+      'fast_location_active_cadence_seconds';
 
   // ============================================================================
   // Configuration Properties
@@ -58,6 +65,15 @@ class LocationTrackingService {
   /// GPS update distance filter for position stream
   double gpsUpdateDistance = 10.0;
 
+  /// Whether private fast GPS updates are enabled
+  bool fastLocationUpdatesEnabled = false;
+
+  /// Distance threshold for fast GPS updates
+  double fastLocationMovementThresholdMeters = 10.0;
+
+  /// Cadence for active-use fast GPS updates
+  int fastLocationActiveCadenceSeconds = 10;
+
   // ============================================================================
   // State Properties
   // ============================================================================
@@ -84,6 +100,11 @@ class LocationTrackingService {
   /// Position stream subscription
   StreamSubscription<Position>? _positionSubscription;
 
+  Timer? _fastLocationTimer;
+  bool _isFastLocationActiveUse = false;
+  DateTime? _lastFastLocationSentAt;
+  Position? _lastFastLocationSentPosition;
+
   // ============================================================================
   // Callback Properties
   // ============================================================================
@@ -100,6 +121,9 @@ class LocationTrackingService {
   /// Called when tracking state changes
   void Function(bool isTracking)? onTrackingStateChanged;
 
+  /// Called when a fast private GPS update should be sent
+  void Function(Position position, String reason)? onFastLocationUpdate;
+
   // ============================================================================
   // Initialization
   // ============================================================================
@@ -125,6 +149,10 @@ class LocationTrackingService {
   /// Check if location permissions are granted
   Future<bool> checkPermissions() async {
     final permission = await Geolocator.checkPermission();
+    if (Platform.isIOS) {
+      return permission == LocationPermission.always;
+    }
+
     return permission == LocationPermission.always ||
         permission == LocationPermission.whileInUse;
   }
@@ -158,6 +186,16 @@ class LocationTrackingService {
       return false;
     }
 
+    if (Platform.isIOS && permission != LocationPermission.always) {
+      permission = await Geolocator.requestPermission();
+      if (permission != LocationPermission.always) {
+        onError?.call(
+          'Background tracking on iOS requires "Always" location access. Enable it in Settings.',
+        );
+        return false;
+      }
+    }
+
     debugPrint('✅ [LocationTracking] Location permissions granted');
     return true;
   }
@@ -178,35 +216,45 @@ class LocationTrackingService {
     for (int attempt = 0; attempt <= retryCount; attempt++) {
       try {
         if (attempt > 0) {
-          debugPrint('🔄 [LocationTracking] Retry attempt $attempt/$retryCount');
+          debugPrint(
+            '🔄 [LocationTracking] Retry attempt $attempt/$retryCount',
+          );
           // Exponential backoff: wait 2^attempt seconds before retry
           await Future.delayed(Duration(seconds: 1 << attempt));
         }
 
         final position = await Geolocator.getCurrentPosition(
-          locationSettings: LocationSettings(
-            accuracy: LocationAccuracy.best,
+          locationSettings: _buildLocationSettings(
             timeLimit: timeLimit,
+            distanceFilter: 0,
           ),
         );
 
         currentPosition = position;
         if (attempt > 0) {
-          debugPrint('✅ [LocationTracking] Position acquired after $attempt retries');
+          debugPrint(
+            '✅ [LocationTracking] Position acquired after $attempt retries',
+          );
         }
         return position;
       } catch (e) {
         final isLastAttempt = attempt == retryCount;
         if (isLastAttempt) {
-          debugPrint('❌ [LocationTracking] Failed to get position after $retryCount retries: $e');
+          debugPrint(
+            '❌ [LocationTracking] Failed to get position after $retryCount retries: $e',
+          );
           // Only call error callback on final failure, and make it user-friendly
           if (e.toString().contains('TimeoutException')) {
-            onError?.call('GPS signal weak. Position stream will continue trying...');
+            onError?.call(
+              'GPS signal weak. Position stream will continue trying...',
+            );
           } else {
             onError?.call('Failed to get GPS position. Check device settings.');
           }
         } else {
-          debugPrint('⚠️ [LocationTracking] Position attempt $attempt failed: $e');
+          debugPrint(
+            '⚠️ [LocationTracking] Position attempt $attempt failed: $e',
+          );
         }
 
         if (isLastAttempt) {
@@ -222,13 +270,35 @@ class LocationTrackingService {
   /// [distanceFilter] - Minimum distance in meters between position updates
   Stream<Position> getPositionStream({double distanceFilter = 10.0}) {
     return Geolocator.getPositionStream(
-      locationSettings: LocationSettings(
-        accuracy: LocationAccuracy.best,
+      locationSettings: _buildLocationSettings(
         distanceFilter: distanceFilter.toInt(),
       ),
     );
   }
 
+  LocationSettings _buildLocationSettings({
+    int distanceFilter = 10,
+    Duration? timeLimit,
+  }) {
+    if (Platform.isIOS) {
+      return AppleSettings(
+        accuracy: LocationAccuracy.best,
+        activityType: ActivityType.fitness,
+        allowBackgroundLocationUpdates: true,
+        distanceFilter: distanceFilter,
+        pauseLocationUpdatesAutomatically: false,
+        showBackgroundLocationIndicator: true,
+        timeLimit: timeLimit,
+      );
+    }
+
+    return LocationSettings(
+      accuracy: LocationAccuracy.best,
+      distanceFilter: distanceFilter,
+      timeLimit: timeLimit,
+    );
+  }
+
   // ============================================================================
   // Tracking Control
   // ============================================================================
@@ -244,16 +314,16 @@ class LocationTrackingService {
   /// GPS tracking works WITHOUT BLE connection - device broadcasts are simply skipped.
   Future<bool> startTracking({double? distanceThreshold}) async {
     if (!_isInitialized) {
-      debugPrint(
-        '⚠️ [LocationTracking] Service not initialized',
-      );
+      debugPrint('⚠️ [LocationTracking] Service not initialized');
       onError?.call('Location tracking service not initialized');
       return false;
     }
 
     // Allow tracking without BLE connection - broadcasts will be skipped
     if (_bleService == null || !_bleService!.isConnected) {
-      debugPrint('ℹ️ [LocationTracking] Starting GPS tracking without BLE connection (broadcasts disabled)');
+      debugPrint(
+        'ℹ️ [LocationTracking] Starting GPS tracking without BLE connection (broadcasts disabled)',
+      );
     }
 
     // Check permissions
@@ -271,17 +341,20 @@ class LocationTrackingService {
 
     // Try to get initial position in background (non-blocking)
     // This will populate currentPosition but won't block tracking startup
-    getCurrentPosition(
-      timeLimit: const Duration(seconds: 10),
-      retryCount: 1,
-    ).then((position) {
-      if (position != null) {
-        debugPrint('✅ [LocationTracking] Initial position acquired in background');
-      }
-    }).catchError((error) {
-      debugPrint('⚠️ [LocationTracking] Background initial position failed: $error');
-      // Not critical - position stream will eventually provide position
-    });
+    getCurrentPosition(timeLimit: const Duration(seconds: 10), retryCount: 1)
+        .then((position) {
+          if (position != null) {
+            debugPrint(
+              '✅ [LocationTracking] Initial position acquired in background',
+            );
+          }
+        })
+        .catchError((error) {
+          debugPrint(
+            '⚠️ [LocationTracking] Background initial position failed: $error',
+          );
+          // Not critical - position stream will eventually provide position
+        });
 
     // Start position stream immediately (don't wait for initial position)
     try {
@@ -296,6 +369,7 @@ class LocationTrackingService {
 
       isTracking = true;
       onTrackingStateChanged?.call(true);
+      _refreshFastLocationTimer();
 
       debugPrint(
         '✅ [LocationTracking] Tracking started with ${threshold}m threshold',
@@ -318,6 +392,7 @@ class LocationTrackingService {
 
     isTracking = false;
     onTrackingStateChanged?.call(false);
+    _refreshFastLocationTimer();
 
     // Reset first position flag so next connection starts fresh
     _firstPositionSet = false;
@@ -361,6 +436,8 @@ class LocationTrackingService {
     // Notify listeners
     onPositionUpdate?.call(position);
 
+    _evaluateFastLocationMovement(position);
+
     // SPECIAL CASE: First stable position after connection
     // Set lat/lon on device WITHOUT broadcasting to mesh network
     if (!_firstPositionSet) {
@@ -378,12 +455,16 @@ class LocationTrackingService {
   /// Updates the device's advertised lat/lon but does NOT send an advertisement.
   void _setInitialPosition(Position position) async {
     if (_bleService == null || !_bleService!.isConnected) {
-      debugPrint('⚠️ [LocationTracking] Cannot set initial position: BLE not connected');
+      debugPrint(
+        '⚠️ [LocationTracking] Cannot set initial position: BLE not connected',
+      );
       return;
     }
 
     try {
-      debugPrint('📍 [LocationTracking] Setting initial position (no broadcast)');
+      debugPrint(
+        '📍 [LocationTracking] Setting initial position (no broadcast)',
+      );
 
       // Update device's advertised location WITHOUT sending advertisement
       await _bleService!.setAdvertLatLon(
@@ -414,7 +495,94 @@ class LocationTrackingService {
   void _checkAndBroadcast(Position position) {
     // Automatic broadcasting disabled
     // Use the manual advert button instead
-    debugPrint('   ⏸️ [LocationTracking] Automatic broadcasting disabled (use advert button)');
+    debugPrint(
+      '   ⏸️ [LocationTracking] Automatic broadcasting disabled (use advert button)',
+    );
+  }
+
+  void setFastLocationActiveUse(bool isActive) {
+    if (_isFastLocationActiveUse == isActive) return;
+    _isFastLocationActiveUse = isActive;
+    _refreshFastLocationTimer();
+  }
+
+  Future<void> setFastLocationUpdatesEnabled(bool enabled) async {
+    fastLocationUpdatesEnabled = enabled;
+    await saveSettings();
+    _refreshFastLocationTimer();
+  }
+
+  Future<void> updateFastLocationMovementThreshold(double meters) async {
+    fastLocationMovementThresholdMeters = meters.clamp(1.0, 1000.0);
+    await saveSettings();
+  }
+
+  Future<void> updateFastLocationActiveCadenceSeconds(int seconds) async {
+    fastLocationActiveCadenceSeconds = seconds.clamp(5, 60);
+    await saveSettings();
+    _refreshFastLocationTimer();
+  }
+
+  void _evaluateFastLocationMovement(Position position) {
+    if (!fastLocationUpdatesEnabled) return;
+    final previous = _lastFastLocationSentPosition;
+    if (previous == null) {
+      _emitFastLocationUpdate(position, reason: 'initial');
+      return;
+    }
+
+    final distance = Geolocator.distanceBetween(
+      previous.latitude,
+      previous.longitude,
+      position.latitude,
+      position.longitude,
+    );
+    if (distance >= fastLocationMovementThresholdMeters) {
+      _emitFastLocationUpdate(position, reason: 'movement');
+    }
+  }
+
+  void _refreshFastLocationTimer() {
+    _fastLocationTimer?.cancel();
+    _fastLocationTimer = null;
+    if (!isTracking ||
+        !fastLocationUpdatesEnabled ||
+        !_isFastLocationActiveUse) {
+      return;
+    }
+
+    _fastLocationTimer = Timer.periodic(
+      Duration(seconds: fastLocationActiveCadenceSeconds),
+      (_) {
+        final position = currentPosition;
+        if (position == null) return;
+        _emitFastLocationUpdate(position, reason: 'active_use');
+      },
+    );
+  }
+
+  void _emitFastLocationUpdate(Position position, {required String reason}) {
+    if (!fastLocationUpdatesEnabled) return;
+
+    final now = DateTime.now();
+    final previous = _lastFastLocationSentPosition;
+    final previousTime = _lastFastLocationSentAt;
+    if (previous != null && previousTime != null) {
+      final distance = Geolocator.distanceBetween(
+        previous.latitude,
+        previous.longitude,
+        position.latitude,
+        position.longitude,
+      );
+      final elapsedMs = now.difference(previousTime).inMilliseconds;
+      if (distance < 1.0 && elapsedMs < 3000) {
+        return;
+      }
+    }
+
+    _lastFastLocationSentPosition = position;
+    _lastFastLocationSentAt = now;
+    onFastLocationUpdate?.call(position, reason);
   }
 
   // ============================================================================
@@ -457,7 +625,9 @@ class LocationTrackingService {
       await _bleService!.sendSelfAdvert(floodMode: true);
 
       debugPrint('✅ [LocationTracking] Manual broadcast successful');
-      debugPrint('   Automatic broadcasts will resume after ${minTimeIntervalSeconds}s');
+      debugPrint(
+        '   Automatic broadcasts will resume after ${minTimeIntervalSeconds}s',
+      );
       onBroadcastSent?.call(position);
 
       return true;
@@ -480,12 +650,24 @@ class LocationTrackingService {
     maxDistanceMeters = prefs.getDouble(_prefKeyMaxDistance) ?? 100.0;
     minTimeIntervalSeconds = prefs.getInt(_prefKeyMinTimeInterval) ?? 30;
     gpsUpdateDistance = prefs.getDouble(_prefKeyGpsUpdateDistance) ?? 10.0;
+    fastLocationUpdatesEnabled =
+        prefs.getBool(_prefKeyFastLocationEnabled) ?? false;
+    fastLocationMovementThresholdMeters =
+        (prefs.getDouble(_prefKeyFastMovementThreshold) ?? gpsUpdateDistance)
+            .clamp(1.0, 1000.0);
+    fastLocationActiveCadenceSeconds =
+        (prefs.getInt(_prefKeyFastActiveCadence) ?? 10).clamp(5, 60);
 
     debugPrint('✅ [LocationTracking] Settings loaded');
     debugPrint('    Min distance: ${minDistanceMeters}m');
     debugPrint('    Max distance: ${maxDistanceMeters}m');
     debugPrint('    Min time interval: ${minTimeIntervalSeconds}s');
     debugPrint('    GPS update distance: ${gpsUpdateDistance}m');
+    debugPrint('    Fast updates enabled: $fastLocationUpdatesEnabled');
+    debugPrint(
+      '    Fast movement threshold: ${fastLocationMovementThresholdMeters}m',
+    );
+    debugPrint('    Fast active cadence: ${fastLocationActiveCadenceSeconds}s');
   }
 
   /// Save settings to SharedPreferences
@@ -497,6 +679,18 @@ class LocationTrackingService {
     await prefs.setInt(_prefKeyMinTimeInterval, minTimeIntervalSeconds);
     await prefs.setDouble(_prefKeyGpsUpdateDistance, gpsUpdateDistance);
     await prefs.setBool(_prefKeyEnabled, isTracking);
+    await prefs.setBool(
+      _prefKeyFastLocationEnabled,
+      fastLocationUpdatesEnabled,
+    );
+    await prefs.setDouble(
+      _prefKeyFastMovementThreshold,
+      fastLocationMovementThresholdMeters,
+    );
+    await prefs.setInt(
+      _prefKeyFastActiveCadence,
+      fastLocationActiveCadenceSeconds,
+    );
 
     debugPrint('✅ [LocationTracking] Settings saved');
   }
@@ -509,6 +703,7 @@ class LocationTrackingService {
   void dispose() {
     debugPrint('🗑️ [LocationTracking] Disposing service');
     _positionSubscription?.cancel();
+    _fastLocationTimer?.cancel();
     _positionSubscription = null;
     _bleService = null;
     _isInitialized = false;

lib/services/map_marker_service.dart

@@ -5,6 +5,7 @@ import 'package:latlong2/latlong.dart';
 import 'package:geolocator/geolocator.dart';
 import '../models/contact.dart';
 import '../models/sar_marker.dart';
+import '../widgets/common/contact_avatar.dart';
 import '../widgets/map/location_pointer.dart';
 
 /// Centralized service for map marker management.
@@ -77,9 +78,15 @@ class MapMarkerService {
                 // Marker icon
                 Container(
                   decoration: BoxDecoration(
-                    color: getContactMarkerColor(contact, context),
-                    shape: BoxShape.circle,
-                    border: Border.all(color: Colors.white, width: 2),
+                    color: Colors.white,
+                    shape: contact.type == ContactType.channel ||
+                            contact.type == ContactType.room
+                        ? BoxShape.rectangle
+                        : BoxShape.circle,
+                    borderRadius: contact.type == ContactType.channel ||
+                            contact.type == ContactType.room
+                        ? BorderRadius.circular(14)
+                        : null,
                     boxShadow: [
                       BoxShadow(
                         color: Colors.black.withValues(alpha: 0.3),
@@ -88,17 +95,8 @@ class MapMarkerService {
                       ),
                     ],
                   ),
-                  padding: const EdgeInsets.all(6),
-                  child: contact.roleEmoji != null
-                      ? Text(
-                          contact.roleEmoji!,
-                          style: const TextStyle(fontSize: 18),
-                        )
-                      : Icon(
-                          getContactMarkerIcon(contact),
-                          color: Colors.white,
-                          size: 18,
-                        ),
+                  padding: const EdgeInsets.all(2),
+                  child: ContactAvatar(contact: contact, radius: 16),
                 ),
                 const SizedBox(height: 2),
                 // Name label (without emoji)

lib/services/mbtiles_service.dart

@@ -1,273 +0,0 @@
-import 'dart:io';
-import 'package:flutter/material.dart';
-import 'package:path_provider/path_provider.dart';
-import 'package:mbtiles/mbtiles.dart';
-
-/// Metadata information extracted from an MBTiles file
-class MbtilesMetadata {
-  final String name;
-  final String? description;
-  final String? version;
-  final String? attribution;
-  final String? bounds; // "minLon,minLat,maxLon,maxLat"
-  final String? center; // "lon,lat,zoom"
-  final int? minZoom;
-  final int? maxZoom;
-  final String? format; // "pbf", "png", "jpg", etc.
-  final String? type; // "overlay", "baselayer"
-  final String? json; // Additional metadata JSON
-  final File file;
-  final int fileSize;
-
-  const MbtilesMetadata({
-    required this.name,
-    this.description,
-    this.version,
-    this.attribution,
-    this.bounds,
-    this.center,
-    this.minZoom,
-    this.maxZoom,
-    this.format,
-    this.type,
-    this.json,
-    required this.file,
-    required this.fileSize,
-  });
-
-  /// Check if this is a vector tile MBTiles file
-  bool get isVector => format == 'pbf' || format == 'mvt';
-
-  /// Parse bounds string into [minLon, minLat, maxLon, maxLat]
-  List<double>? get boundsCoordinates {
-    if (bounds == null) return null;
-    try {
-      final parts = bounds!.split(',');
-      if (parts.length != 4) return null;
-      return parts.map((s) => double.parse(s.trim())).toList();
-    } catch (e) {
-      debugPrint('Error parsing bounds: $e');
-      return null;
-    }
-  }
-
-  /// Parse center string into [lon, lat, zoom]
-  List<double>? get centerCoordinates {
-    if (center == null) return null;
-    try {
-      final parts = center!.split(',');
-      if (parts.length < 2) return null;
-      return parts.map((s) => double.parse(s.trim())).toList();
-    } catch (e) {
-      debugPrint('Error parsing center: $e');
-      return null;
-    }
-  }
-
-  /// Get file size in human-readable format
-  String get fileSizeFormatted {
-    if (fileSize < 1024) {
-      return '$fileSize B';
-    } else if (fileSize < 1024 * 1024) {
-      return '${(fileSize / 1024).toStringAsFixed(1)} KB';
-    } else if (fileSize < 1024 * 1024 * 1024) {
-      return '${(fileSize / (1024 * 1024)).toStringAsFixed(1)} MB';
-    } else {
-      return '${(fileSize / (1024 * 1024 * 1024)).toStringAsFixed(2)} GB';
-    }
-  }
-}
-
-/// Service for managing MBTiles files for offline vector maps
-class MbtilesService {
-  static const String _mbtilesDirectory = 'offline_maps';
-
-  /// Get the directory where MBTiles files are stored
-  Future<Directory> getMbtilesDirectory() async {
-    final appDocDir = await getApplicationDocumentsDirectory();
-    final mbtilesDir = Directory('${appDocDir.path}/$_mbtilesDirectory');
-
-    // Create directory if it doesn't exist
-    if (!await mbtilesDir.exists()) {
-      await mbtilesDir.create(recursive: true);
-    }
-
-    return mbtilesDir;
-  }
-
-  /// List all MBTiles files in the offline maps directory
-  Future<List<File>> listMbtilesFiles() async {
-    final dir = await getMbtilesDirectory();
-
-    try {
-      final files = await dir
-          .list()
-          .where((entity) => entity is File && entity.path.endsWith('.mbtiles'))
-          .map((entity) => entity as File)
-          .toList();
-
-      return files;
-    } catch (e) {
-      debugPrint('Error listing MBTiles files: $e');
-      return [];
-    }
-  }
-
-  /// Get metadata from an MBTiles file
-  Future<MbtilesMetadata?> getMetadata(File file) async {
-    try {
-      // Check if file exists
-      if (!await file.exists()) {
-        debugPrint('MBTiles file does not exist: ${file.path}');
-        return null;
-      }
-
-      // Get file size
-      final fileSize = await file.length();
-
-      // Open MBTiles file
-      final mbtiles = MbTiles(mbtilesPath: file.path);
-
-      // Get metadata from MBTiles
-      final metadata = mbtiles.getMetadata();
-
-      // Convert bounds object to string if available
-      String? boundsStr;
-      if (metadata.bounds != null) {
-        boundsStr = metadata.bounds.toString();
-      }
-
-      return MbtilesMetadata(
-        name: metadata.name,
-        description: metadata.description,
-        version: metadata.version?.toString(),
-        attribution: null, // Not available in new API
-        bounds: boundsStr,
-        center: null, // Not available in new API
-        minZoom: metadata.minZoom?.toInt(),
-        maxZoom: metadata.maxZoom?.toInt(),
-        format: metadata.format,
-        type: metadata.type?.name,
-        json: null, // Not available in new API
-        file: file,
-        fileSize: fileSize,
-      );
-    } catch (e) {
-      debugPrint('Error reading MBTiles metadata from ${file.path}: $e');
-      return null;
-    }
-  }
-
-  /// Get metadata for all MBTiles files
-  Future<List<MbtilesMetadata>> getAllMetadata() async {
-    final files = await listMbtilesFiles();
-    final metadataList = <MbtilesMetadata>[];
-
-    for (final file in files) {
-      final metadata = await getMetadata(file);
-      if (metadata != null) {
-        metadataList.add(metadata);
-      }
-    }
-
-    return metadataList;
-  }
-
-  /// Import an MBTiles file from an external location
-  Future<File?> importMbtilesFile(String sourcePath) async {
-    try {
-      final sourceFile = File(sourcePath);
-
-      // Verify source file exists
-      if (!await sourceFile.exists()) {
-        debugPrint('Source file does not exist: $sourcePath');
-        return null;
-      }
-
-      // Get destination directory
-      final destDir = await getMbtilesDirectory();
-      final fileName = _getFileName(sourceFile);
-      final destPath = '${destDir.path}/$fileName';
-
-      // Copy file to destination
-      final destFile = await sourceFile.copy(destPath);
-      debugPrint('Imported MBTiles file to: $destPath');
-
-      return destFile;
-    } catch (e) {
-      debugPrint('Error importing MBTiles file: $e');
-      return null;
-    }
-  }
-
-  /// Delete an MBTiles file
-  Future<bool> deleteMbtilesFile(File file) async {
-    try {
-      if (await file.exists()) {
-        await file.delete();
-        debugPrint('Deleted MBTiles file: ${file.path}');
-        return true;
-      }
-      return false;
-    } catch (e) {
-      debugPrint('Error deleting MBTiles file: $e');
-      return false;
-    }
-  }
-
-  /// Check if data in MBTiles is gzip compressed
-  Future<bool> isGzipCompressed(File file) async {
-    try {
-      // Open MBTiles and check a sample tile
-      final mbtiles = MbTiles(mbtilesPath: file.path);
-
-      // Try to get metadata to check for compression hints
-      final metadata = mbtiles.getMetadata();
-      final format = metadata.format;
-
-      // For Geofabrik files, format is 'pbf' and data is gzipped
-      // We can infer this from common patterns, but ideally we'd check actual tile data
-      if (format == 'pbf') {
-        // Geofabrik MBTiles are typically gzipped
-        // Could also check tile data headers, but this is a reasonable heuristic
-        return true;
-      }
-
-      return false;
-    } catch (e) {
-      debugPrint('Error checking gzip compression: $e');
-      return false;
-    }
-  }
-
-  /// Determine the vector tile schema from metadata
-  String? getVectorSchema(MbtilesMetadata metadata) {
-    // Try to infer schema from metadata
-    final json = metadata.json;
-    if (json != null) {
-      if (json.contains('shortbread')) {
-        return 'shortbread';
-      } else if (json.contains('openmaptiles')) {
-        return 'openmaptiles';
-      }
-    }
-
-    // Check description
-    final description = metadata.description?.toLowerCase();
-    if (description != null) {
-      if (description.contains('shortbread')) {
-        return 'shortbread';
-      } else if (description.contains('openmaptiles')) {
-        return 'openmaptiles';
-      }
-    }
-
-    // Default to unknown
-    return null;
-  }
-
-  /// Helper: Get file name from path
-  String _getFileName(File file) {
-    return file.path.split(Platform.pathSeparator).last;
-  }
-}

lib/services/mesh_map_nodes_service.dart

@@ -1,5 +1,7 @@
+import 'dart:async';
 import 'dart:convert';
 import 'package:http/http.dart' as http;
+import 'package:shared_preferences/shared_preferences.dart';
 
 class MeshMapNode {
   final int type;
@@ -31,23 +33,40 @@ class MeshMapNode {
 }
 
 class MeshMapNodesService {
-  static const String _nodesEndpoint = 'https://api.meshcore.nz/api/v1/map/nodes';
-  static const Duration _cacheTtl = Duration(minutes: 2);
+  static const String _nodesEndpoint =
+      'https://api.meshcore.nz/api/v1/map/nodes';
+  static const int repeaterType = 1;
+  static const Duration _cacheTtl = Duration(hours: 24);
+  static const Duration traceCacheTtl = _cacheTtl;
+  static const Duration traceTimeout = Duration(seconds: 30);
+  static const String _cacheKey = 'mesh_map_nodes_cache_v1';
+  static const String _cacheTimestampKey = 'mesh_map_nodes_cache_timestamp_v1';
   static List<MeshMapNode>? _cachedNodes;
   static DateTime? _cachedAt;
+  static Future<void>? _ongoingSync;
 
-  static Future<List<MeshMapNode>> fetchNodes({bool forceRefresh = false}) async {
+  static Future<List<MeshMapNode>> fetchNodes({
+    bool forceRefresh = false,
+    Duration cacheTtl = _cacheTtl,
+    bool allowNetwork = true,
+    http.Client? client,
+  }) async {
     final now = DateTime.now();
+    final cached = await loadCachedNodes(cacheTtl: cacheTtl);
     if (!forceRefresh &&
-        _cachedNodes != null &&
+        cached.isNotEmpty &&
         _cachedAt != null &&
-        now.difference(_cachedAt!) < _cacheTtl) {
-      return _cachedNodes!;
+        now.difference(_cachedAt!) < cacheTtl) {
+      return cached;
     }
 
-    final response = await http
+    if (!allowNetwork) {
+      return cached;
+    }
+
+    final response = await (client ?? http.Client())
         .get(Uri.parse(_nodesEndpoint))
-        .timeout(const Duration(seconds: 12));
+        .timeout(traceTimeout);
     if (response.statusCode < 200 || response.statusCode >= 300) {
       throw Exception('Map nodes API returned ${response.statusCode}');
     }
@@ -58,11 +77,138 @@ class MeshMapNodesService {
     final nodes = nodesRaw
         .whereType<Map<String, dynamic>>()
         .map(MeshMapNode.fromJson)
-        .where((n) => n.publicKey.isNotEmpty && n.latitude != 0 && n.longitude != 0)
+        .where(
+          (n) => n.publicKey.isNotEmpty && n.latitude != 0 && n.longitude != 0,
+        )
         .toList();
 
-    _cachedNodes = nodes;
-    _cachedAt = now;
+    await _storeCache(nodes, cachedAt: now);
     return nodes;
   }
+
+  static Future<List<MeshMapNode>> loadCachedNodes({
+    Duration cacheTtl = _cacheTtl,
+  }) async {
+    final now = DateTime.now();
+    if (_cachedNodes != null &&
+        _cachedAt != null &&
+        now.difference(_cachedAt!) < cacheTtl) {
+      return _cachedNodes!;
+    }
+
+    final prefs = await SharedPreferences.getInstance();
+    final cachedAtMs = prefs.getInt(_cacheTimestampKey);
+    final cachedJson = prefs.getString(_cacheKey);
+    if (cachedAtMs == null || cachedJson == null) {
+      _cachedNodes = null;
+      _cachedAt = null;
+      return const [];
+    }
+
+    final cachedAt = DateTime.fromMillisecondsSinceEpoch(cachedAtMs);
+    if (now.difference(cachedAt) >= cacheTtl) {
+      _cachedNodes = null;
+      _cachedAt = cachedAt;
+      return const [];
+    }
+
+    final decoded = jsonDecode(cachedJson) as List<dynamic>;
+    final nodes = decoded
+        .whereType<Map<String, dynamic>>()
+        .map(MeshMapNode.fromJson)
+        .where(
+          (n) => n.publicKey.isNotEmpty && n.latitude != 0 && n.longitude != 0,
+        )
+        .toList();
+    _cachedNodes = nodes;
+    _cachedAt = cachedAt;
+    return nodes;
+  }
+
+  static Future<bool> hasFreshCache({Duration cacheTtl = _cacheTtl}) async {
+    final nodes = await loadCachedNodes(cacheTtl: cacheTtl);
+    return nodes.isNotEmpty;
+  }
+
+  static Future<void> syncInBackgroundIfStale({
+    Duration cacheTtl = _cacheTtl,
+    http.Client? client,
+  }) async {
+    final now = DateTime.now();
+    if (_cachedAt != null && now.difference(_cachedAt!) < cacheTtl) {
+      return;
+    }
+
+    final cached = await loadCachedNodes(cacheTtl: cacheTtl);
+    if (cached.isNotEmpty && _cachedAt != null) {
+      return;
+    }
+
+    if (_ongoingSync != null) {
+      return _ongoingSync!;
+    }
+
+    _ongoingSync = () async {
+      try {
+        await fetchNodes(
+          forceRefresh: true,
+          cacheTtl: cacheTtl,
+          allowNetwork: true,
+          client: client,
+        );
+      } catch (_) {
+        // Background refresh is best-effort only.
+      } finally {
+        _ongoingSync = null;
+      }
+    }();
+
+    return _ongoingSync!;
+  }
+
+  static Future<void> clearCache() async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.remove(_cacheKey);
+    await prefs.remove(_cacheTimestampKey);
+    _cachedNodes = null;
+    _cachedAt = null;
+  }
+
+  static Future<DateTime?> cachedAt() async {
+    if (_cachedAt != null) return _cachedAt;
+    final prefs = await SharedPreferences.getInstance();
+    final cachedAtMs = prefs.getInt(_cacheTimestampKey);
+    if (cachedAtMs == null) return null;
+    _cachedAt = DateTime.fromMillisecondsSinceEpoch(cachedAtMs);
+    return _cachedAt;
+  }
+
+  static bool isRepeater(MeshMapNode node) => node.type == repeaterType;
+
+  static Future<void> _storeCache(
+    List<MeshMapNode> nodes, {
+    required DateTime cachedAt,
+  }) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setString(
+      _cacheKey,
+      jsonEncode(
+        nodes
+            .map(
+              (node) => {
+                'type': node.type,
+                'name': node.name,
+                'public_key': node.publicKey,
+                'latitude': node.latitude,
+                'longitude': node.longitude,
+                'updated_at': node.updatedAtMs,
+              },
+            )
+            .toList(),
+      ),
+    );
+    await prefs.setInt(_cacheTimestampKey, cachedAt.millisecondsSinceEpoch);
+    _cachedNodes = nodes;
+    _cachedAt = cachedAt;
+  }
 }

lib/services/message_destination_preferences.dart

@@ -7,6 +7,7 @@ class MessageDestinationPreferences {
   static const String _recipientPublicKeyKey = 'message_recipient_public_key';
 
   /// Destination types
+  static const String destinationTypeAll = 'all';
   static const String destinationTypeChannel = 'channel';
   static const String destinationTypeContact = 'contact';
   static const String destinationTypeRoom = 'room';
@@ -24,14 +25,11 @@ class MessageDestinationPreferences {
 
     final publicKey = prefs.getString(_recipientPublicKeyKey);
 
-    return {
-      'type': type,
-      'publicKey': ?publicKey,
-    };
+    return {'type': type, 'publicKey': ?publicKey};
   }
 
   /// Save the selected destination
-  /// [type] - one of: destinationTypeChannel, destinationTypeContact, destinationTypeRoom
+  /// [type] - one of: destinationTypeAll, destinationTypeChannel, destinationTypeContact, destinationTypeRoom
   /// [recipientPublicKey] - hex string of recipient's public key (required for contact/room)
   static Future<void> setDestination(
     String type, {
@@ -58,6 +56,8 @@ class MessageDestinationPreferences {
   /// Get display name for destination type
   static String getDestinationTypeName(String type) {
     switch (type) {
+      case destinationTypeAll:
+        return 'All';
       case destinationTypeChannel:
         return 'Channel';
       case destinationTypeContact:

lib/services/message_storage_service.dart

@@ -2,15 +2,33 @@ import 'dart:convert';
 import 'package:flutter/foundation.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import '../models/message.dart';
+import '../models/message_contact_location.dart';
+import '../models/message_reception_details.dart';
+import '../models/message_transfer_details.dart';
+import '../models/message_route_metadata.dart';
 import 'package:latlong2/latlong.dart';
 
 /// Service for persisting messages to local storage
 class MessageStorageService {
   static const String _messagesKey = 'stored_messages';
+  static const String _messageContactLocationsKey =
+      'stored_message_contact_locations';
+  static const String _messageReceptionDetailsKey =
+      'stored_message_reception_details';
+  static const String _messageTransferDetailsKey =
+      'stored_message_transfer_details';
+  static const String _messageRouteMetadataKey =
+      'stored_message_route_metadata';
   static const int _maxStoredMessages = 1000; // Store up to 1000 messages
 
   /// Save messages to persistent storage
-  Future<void> saveMessages(List<Message> messages) async {
+  Future<void> saveMessages(
+    List<Message> messages, {
+    Map<String, MessageContactLocation> messageContactLocations = const {},
+    Map<String, MessageReceptionDetails> messageReceptionDetails = const {},
+    Map<String, MessageTransferDetails> messageTransferDetails = const {},
+    Map<String, MessageRouteMetadata> messageRouteMetadata = const {},
+  }) async {
     try {
       final prefs = await SharedPreferences.getInstance();
 
@@ -24,6 +42,49 @@ class MessageStorageService {
 
       final jsonString = jsonEncode(limitedList);
       await prefs.setString(_messagesKey, jsonString);
+      final retainedMessageIds = limitedList
+          .map((entry) => entry['id'] as String)
+          .toSet();
+      final locationJson = <String, dynamic>{};
+      final receptionJson = <String, dynamic>{};
+      final transferJson = <String, dynamic>{};
+      final routeMetadataJson = <String, dynamic>{};
+      for (final entry in messageContactLocations.entries) {
+        if (retainedMessageIds.contains(entry.key)) {
+          locationJson[entry.key] = entry.value.toJson();
+        }
+      }
+      for (final entry in messageReceptionDetails.entries) {
+        if (retainedMessageIds.contains(entry.key)) {
+          receptionJson[entry.key] = entry.value.toJson();
+        }
+      }
+      for (final entry in messageTransferDetails.entries) {
+        if (retainedMessageIds.contains(entry.key)) {
+          transferJson[entry.key] = entry.value.toJson();
+        }
+      }
+      for (final entry in messageRouteMetadata.entries) {
+        if (retainedMessageIds.contains(entry.key)) {
+          routeMetadataJson[entry.key] = entry.value.toJson();
+        }
+      }
+      await prefs.setString(
+        _messageContactLocationsKey,
+        jsonEncode(locationJson),
+      );
+      await prefs.setString(
+        _messageReceptionDetailsKey,
+        jsonEncode(receptionJson),
+      );
+      await prefs.setString(
+        _messageTransferDetailsKey,
+        jsonEncode(transferJson),
+      );
+      await prefs.setString(
+        _messageRouteMetadataKey,
+        jsonEncode(routeMetadataJson),
+      );
 
       debugPrint(
         '✅ [MessageStorage] Saved ${limitedList.length} messages to storage',
@@ -33,6 +94,122 @@ class MessageStorageService {
     }
   }
 
+  Future<Map<String, MessageContactLocation>>
+  loadMessageContactLocations() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final jsonString = prefs.getString(_messageContactLocationsKey);
+      if (jsonString == null || jsonString.isEmpty) {
+        return const {};
+      }
+
+      final decoded = jsonDecode(jsonString);
+      if (decoded is! Map<String, dynamic>) {
+        return const {};
+      }
+
+      final result = <String, MessageContactLocation>{};
+      for (final entry in decoded.entries) {
+        final value = entry.value;
+        if (value is! Map<String, dynamic>) continue;
+        final snapshot = MessageContactLocation.fromJson(value);
+        if (snapshot != null) {
+          result[entry.key] = snapshot;
+        }
+      }
+      return result;
+    } catch (e) {
+      debugPrint('❌ [MessageStorage] Error loading contact locations: $e');
+      return const {};
+    }
+  }
+
+  Future<Map<String, MessageReceptionDetails>>
+  loadMessageReceptionDetails() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final jsonString = prefs.getString(_messageReceptionDetailsKey);
+      if (jsonString == null || jsonString.isEmpty) {
+        return const {};
+      }
+
+      final decoded = jsonDecode(jsonString);
+      if (decoded is! Map<String, dynamic>) {
+        return const {};
+      }
+
+      final result = <String, MessageReceptionDetails>{};
+      for (final entry in decoded.entries) {
+        final value = entry.value;
+        if (value is! Map<String, dynamic>) continue;
+        final snapshot = MessageReceptionDetails.fromJson(value);
+        if (snapshot != null) {
+          result[entry.key] = snapshot;
+        }
+      }
+      return result;
+    } catch (e) {
+      debugPrint('❌ [MessageStorage] Error loading reception details: $e');
+      return const {};
+    }
+  }
+
+  Future<Map<String, MessageTransferDetails>>
+  loadMessageTransferDetails() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final jsonString = prefs.getString(_messageTransferDetailsKey);
+      if (jsonString == null || jsonString.isEmpty) {
+        return const {};
+      }
+
+      final decoded = jsonDecode(jsonString);
+      if (decoded is! Map<String, dynamic>) {
+        return const {};
+      }
+
+      final result = <String, MessageTransferDetails>{};
+      for (final entry in decoded.entries) {
+        final value = entry.value;
+        if (value is! Map<String, dynamic>) continue;
+        final details = MessageTransferDetails.fromJson(value);
+        if (details != null) {
+          result[entry.key] = details;
+        }
+      }
+      return result;
+    } catch (e) {
+      debugPrint('❌ [MessageStorage] Error loading transfer details: $e');
+      return const {};
+    }
+  }
+
+  Future<Map<String, MessageRouteMetadata>> loadMessageRouteMetadata() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final jsonString = prefs.getString(_messageRouteMetadataKey);
+      if (jsonString == null || jsonString.isEmpty) {
+        return const {};
+      }
+
+      final decoded = jsonDecode(jsonString);
+      if (decoded is! Map<String, dynamic>) {
+        return const {};
+      }
+
+      final result = <String, MessageRouteMetadata>{};
+      for (final entry in decoded.entries) {
+        final value = entry.value;
+        if (value is! Map<String, dynamic>) continue;
+        result[entry.key] = MessageRouteMetadata.fromJson(value);
+      }
+      return result;
+    } catch (e) {
+      debugPrint('❌ [MessageStorage] Error loading route metadata: $e');
+      return const {};
+    }
+  }
+
   /// Load messages from persistent storage
   Future<List<Message>> loadMessages() async {
     try {
@@ -66,6 +243,10 @@ class MessageStorageService {
     try {
       final prefs = await SharedPreferences.getInstance();
       await prefs.remove(_messagesKey);
+      await prefs.remove(_messageContactLocationsKey);
+      await prefs.remove(_messageReceptionDetailsKey);
+      await prefs.remove(_messageTransferDetailsKey);
+      await prefs.remove(_messageRouteMetadataKey);
       debugPrint('✅ [MessageStorage] Cleared all stored messages');
     } catch (e) {
       debugPrint('❌ [MessageStorage] Error clearing messages: $e');

lib/services/messaging_route_preferences.dart

@@ -0,0 +1,46 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+class MessagingRoutePreferences {
+  static const bool defaultAutoRouteRotationEnabled = false;
+  static const bool defaultClearPathOnMaxRetry = false;
+  static const bool defaultNearestRelayFallbackEnabled = true;
+
+  static const String _autoRouteRotationKey =
+      'messaging_auto_route_rotation_enabled';
+  static const String _clearPathOnMaxRetryKey =
+      'messaging_clear_path_on_max_retry';
+  static const String _nearestRelayFallbackKey =
+      'messaging_nearest_relay_fallback_enabled';
+
+  static Future<bool> getAutoRouteRotationEnabled() async {
+    final prefs = await SharedPreferences.getInstance();
+    return prefs.getBool(_autoRouteRotationKey) ??
+        defaultAutoRouteRotationEnabled;
+  }
+
+  static Future<void> setAutoRouteRotationEnabled(bool enabled) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setBool(_autoRouteRotationKey, enabled);
+  }
+
+  static Future<bool> getClearPathOnMaxRetry() async {
+    final prefs = await SharedPreferences.getInstance();
+    return prefs.getBool(_clearPathOnMaxRetryKey) ?? defaultClearPathOnMaxRetry;
+  }
+
+  static Future<void> setClearPathOnMaxRetry(bool enabled) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setBool(_clearPathOnMaxRetryKey, enabled);
+  }
+
+  static Future<bool> getNearestRelayFallbackEnabled() async {
+    final prefs = await SharedPreferences.getInstance();
+    return prefs.getBool(_nearestRelayFallbackKey) ??
+        defaultNearestRelayFallbackEnabled;
+  }
+
+  static Future<void> setNearestRelayFallbackEnabled(bool enabled) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setBool(_nearestRelayFallbackKey, enabled);
+  }
+}

lib/services/nearest_router_selector.dart

@@ -0,0 +1,69 @@
+import 'package:geolocator/geolocator.dart';
+
+import '../models/contact.dart';
+
+class NearestRouterSelector {
+  const NearestRouterSelector();
+
+  Contact? select({
+    required Position? senderPosition,
+    required List<Contact> repeaters,
+    required Contact recipient,
+  }) {
+    if (senderPosition == null) {
+      return null;
+    }
+
+    final eligible = repeaters.where((contact) {
+      if (contact.publicKeyHex == recipient.publicKeyHex) {
+        return false;
+      }
+      if (!contact.isRecentlySeen) {
+        return false;
+      }
+      return contact.displayLocation != null;
+    }).toList();
+    if (eligible.isEmpty) {
+      return null;
+    }
+
+    eligible.sort((a, b) {
+      final locationA = a.displayLocation!;
+      final locationB = b.displayLocation!;
+      final distanceA = Geolocator.distanceBetween(
+        senderPosition.latitude,
+        senderPosition.longitude,
+        locationA.latitude,
+        locationA.longitude,
+      );
+      final distanceB = Geolocator.distanceBetween(
+        senderPosition.latitude,
+        senderPosition.longitude,
+        locationB.latitude,
+        locationB.longitude,
+      );
+      final distanceCompare = distanceA.compareTo(distanceB);
+      if (distanceCompare != 0) {
+        return distanceCompare;
+      }
+
+      final advertCompare = b.lastAdvert.compareTo(a.lastAdvert);
+      if (advertCompare != 0) {
+        return advertCompare;
+      }
+
+      final hopCompare = a.routeHopCount.compareTo(b.routeHopCount);
+      if (hopCompare != 0) {
+        return hopCompare;
+      }
+
+      final nameCompare = a.advName.compareTo(b.advName);
+      if (nameCompare != 0) {
+        return nameCompare;
+      }
+      return a.publicKeyHex.compareTo(b.publicKeyHex);
+    });
+
+    return eligible.first;
+  }
+}

lib/services/notification_service.dart

@@ -58,7 +58,6 @@ class NotificationService {
         requestAlertPermission: true,
         requestBadgePermission: true,
         requestSoundPermission: true,
-        requestCriticalPermission: true, // For urgent SAR notifications
       );
 
       // Combined initialization settings
@@ -100,8 +99,6 @@ class NotificationService {
           alert: true,
           badge: true,
           sound: true,
-          critical:
-              true, // Request critical alert permission for urgent SAR notifications
         );
         _permissionGranted = granted ?? false;
         debugPrint(
@@ -274,8 +271,7 @@ class NotificationService {
         badgeNumber: 1,
         threadIdentifier: 'sar_markers',
         categoryIdentifier: 'SAR_ALERT',
-        interruptionLevel:
-            InterruptionLevel.critical, // Critical alert (bypasses silent mode)
+        interruptionLevel: InterruptionLevel.timeSensitive,
       );
 
       // Combined notification details
@@ -406,10 +402,13 @@ class NotificationService {
           (DateTime.now().millisecondsSinceEpoch % 1000);
 
       // Build notification title and body
+      final resolvedChannelName = channelName?.trim().isNotEmpty == true
+          ? channelName!.trim()
+          : (localizations?.publicChannel ?? 'Public');
       final title = isChannelMessage
           ? (localizations != null
-                ? '${localizations.channel}: ${channelName ?? "Public"}'
-                : 'Channel: ${channelName ?? "Public"}')
+                ? '${localizations.channel}: $resolvedChannelName'
+                : 'Channel: $resolvedChannelName')
           : (localizations != null
                 ? '${localizations.newMessage} ${localizations.from} $senderName'
                 : 'New message from $senderName');
@@ -554,7 +553,7 @@ class NotificationService {
       final title = localizations?.updateAvailable ?? 'App Update Available';
       final body = localizations != null
           ? '${localizations.currentVersion}: $currentVersion\n'
-              '${localizations.latestVersion}: $latestVersion'
+                '${localizations.latestVersion}: $latestVersion'
           : 'Current: $currentVersion\nLatest: $latestVersion';
 
       // Android notification details

lib/services/packet_capture_storage_service.dart

@@ -61,6 +61,9 @@ class PacketCaptureStorageService {
   File? _file;
 
   Future<File> _resolveFile() async {
+    if (kIsWeb) {
+      throw UnsupportedError('Packet capture file storage is not supported on web');
+    }
     if (_file != null) return _file!;
     final dir = await getApplicationSupportDirectory();
     final file = File('${dir.path}/$_fileName');
@@ -73,6 +76,7 @@ class PacketCaptureStorageService {
 
   Future<void> appendLogs(List<BlePacketLog> logs) async {
     if (logs.isEmpty) return;
+    if (kIsWeb) return;
     try {
       final file = await _resolveFile();
       final sink = file.openWrite(mode: FileMode.append);
@@ -98,6 +102,7 @@ class PacketCaptureStorageService {
   }
 
   Future<List<StoredPacketCapture>> loadRecent({int limit = 500}) async {
+    if (kIsWeb) return const [];
     try {
       final file = await _resolveFile();
       if (!await file.exists()) return const [];
@@ -116,6 +121,7 @@ class PacketCaptureStorageService {
   }
 
   Future<int> count() async {
+    if (kIsWeb) return 0;
     try {
       final file = await _resolveFile();
       if (!await file.exists()) return 0;
@@ -127,6 +133,7 @@ class PacketCaptureStorageService {
   }
 
   Future<void> clear() async {
+    if (kIsWeb) return;
     try {
       final file = await _resolveFile();
       if (await file.exists()) {

lib/services/path_history_service.dart

@@ -0,0 +1,273 @@
+import 'dart:convert';
+
+import 'package:flutter/foundation.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import '../models/contact.dart';
+import '../models/path_history.dart';
+import '../models/path_selection.dart';
+
+class PathHistoryService {
+  static const String _storageKey = 'contact_path_history_v1';
+  static const int _maxDirectPaths = 20;
+  static const int _topRotationCount = 3;
+
+  final Map<String, ContactPathHistory> _cache = {};
+  bool _isLoaded = false;
+
+  Future<void> initialize() async {
+    if (_isLoaded) return;
+    final prefs = await SharedPreferences.getInstance();
+    final raw = prefs.getString(_storageKey);
+    if (raw == null || raw.isEmpty) {
+      _isLoaded = true;
+      return;
+    }
+
+    try {
+      final decoded = jsonDecode(raw);
+      if (decoded is Map<String, dynamic>) {
+        for (final entry in decoded.entries) {
+          final value = entry.value;
+          if (value is Map<String, dynamic>) {
+            _cache[entry.key] = ContactPathHistory.fromJson(entry.key, value);
+          }
+        }
+      }
+    } catch (error) {
+      debugPrint('⚠️ [PathHistoryService] Failed to load history: $error');
+    }
+    _isLoaded = true;
+  }
+
+  Future<void> recordLearnedPath(Contact contact) async {
+    await initialize();
+    if (!contact.routeHasPath || contact.routeHopCount <= 0) {
+      return;
+    }
+
+    final history = _historyFor(contact.publicKeyHex);
+    final signature = _signature(contact.routePathBytes);
+    final existing = _findDirectPath(history.directPaths, signature);
+    final updated = PathRecord(
+      pathBytes: contact.routePathBytes.toList(),
+      hopCount: contact.routeHopCount,
+      hashSize: contact.routeHashSize,
+      successCount: existing?.successCount ?? 0,
+      failureCount: existing?.failureCount ?? 0,
+      lastRoundTripTimeMs: existing?.lastRoundTripTimeMs ?? 0,
+      lastUsedAt: DateTime.now(),
+    );
+
+    await _saveHistory(
+      contact.publicKeyHex,
+      history.copyWith(
+        directPaths: _upsertDirectPath(history.directPaths, updated),
+      ),
+    );
+  }
+
+  Future<void> recordReceivedBytePath(
+    String contactPublicKeyHex,
+    List<int> pathBytes,
+    int hashSize,
+  ) async {
+    await initialize();
+    if (pathBytes.isEmpty) {
+      return;
+    }
+    if (hashSize < 1 || hashSize > 3) {
+      return;
+    }
+    if (pathBytes.length % hashSize != 0) {
+      return;
+    }
+
+    final history = _historyFor(contactPublicKeyHex);
+    final signature = pathBytes
+        .map((byte) => byte.toRadixString(16).padLeft(2, '0'))
+        .join();
+    final existing = _findDirectPath(history.directPaths, signature);
+    final updated = PathRecord(
+      pathBytes: List<int>.from(pathBytes),
+      hopCount: pathBytes.length ~/ hashSize,
+      hashSize: hashSize,
+      successCount: existing?.successCount ?? 0,
+      failureCount: existing?.failureCount ?? 0,
+      lastRoundTripTimeMs: existing?.lastRoundTripTimeMs ?? 0,
+      lastUsedAt: DateTime.now(),
+    );
+
+    await _saveHistory(
+      contactPublicKeyHex,
+      history.copyWith(
+        directPaths: _upsertDirectPath(history.directPaths, updated),
+      ),
+    );
+  }
+
+  Future<PathSelection> getSelectionForContact(
+    Contact contact, {
+    required bool autoRouteRotationEnabled,
+  }) async {
+    await initialize();
+    await recordLearnedPath(contact);
+
+    if (contact.routeHasPath && contact.routeHopCount > 0) {
+      return PathSelection(
+        mode: PathSelectionMode.directCurrent,
+        pathBytes: Uint8List.fromList(contact.routePathBytes),
+        hopCount: contact.routeHopCount,
+        hashSize: contact.routeHashSize,
+      );
+    }
+
+    if (!autoRouteRotationEnabled) {
+      return PathSelection.flood();
+    }
+
+    final history = _historyFor(contact.publicKeyHex);
+    final ranked = List<PathRecord>.from(history.directPaths)
+      ..sort(_comparePathRecords);
+    final topPaths = ranked.take(_topRotationCount).toList();
+    if (topPaths.isEmpty) {
+      final nextFloodHistory = history.copyWith(
+        rotationIndex: history.rotationIndex + 1,
+      );
+      await _saveHistory(contact.publicKeyHex, nextFloodHistory);
+      return PathSelection.flood();
+    }
+
+    final selections =
+        topPaths
+            .map(
+              (record) => PathSelection(
+                mode: PathSelectionMode.directHistorical,
+                pathBytes: Uint8List.fromList(record.pathBytes),
+                hopCount: record.hopCount,
+                hashSize: record.hashSize,
+              ),
+            )
+            .toList()
+          ..add(PathSelection.flood());
+
+    final index = history.rotationIndex % selections.length;
+    final updatedHistory = history.copyWith(
+      rotationIndex: history.rotationIndex + 1,
+    );
+    await _saveHistory(contact.publicKeyHex, updatedHistory);
+    return selections[index];
+  }
+
+  Future<void> recordPathResult(
+    String contactPublicKeyHex,
+    PathSelection selection, {
+    required bool success,
+    int? roundTripTimeMs,
+  }) async {
+    await initialize();
+    final history = _historyFor(contactPublicKeyHex);
+    if (selection.usesFlood) {
+      final current = history.floodStats;
+      await _saveHistory(
+        contactPublicKeyHex,
+        history.copyWith(
+          floodStats: current.copyWith(
+            successCount: current.successCount + (success ? 1 : 0),
+            failureCount: current.failureCount + (success ? 0 : 1),
+            lastRoundTripTimeMs: success
+                ? (roundTripTimeMs ?? current.lastRoundTripTimeMs)
+                : current.lastRoundTripTimeMs,
+            lastUsedAt: DateTime.now(),
+          ),
+        ),
+      );
+      return;
+    }
+
+    final signature = _signature(selection.pathBytes);
+    final existing = _findDirectPath(history.directPaths, signature);
+    final updated = PathRecord(
+      pathBytes: selection.pathBytes.toList(),
+      hopCount: selection.hopCount,
+      hashSize: selection.hashSize,
+      successCount: (existing?.successCount ?? 0) + (success ? 1 : 0),
+      failureCount: (existing?.failureCount ?? 0) + (success ? 0 : 1),
+      lastRoundTripTimeMs: success
+          ? (roundTripTimeMs ?? existing?.lastRoundTripTimeMs ?? 0)
+          : (existing?.lastRoundTripTimeMs ?? 0),
+      lastUsedAt: DateTime.now(),
+    );
+    await _saveHistory(
+      contactPublicKeyHex,
+      history.copyWith(
+        directPaths: _upsertDirectPath(history.directPaths, updated),
+      ),
+    );
+  }
+
+  ContactPathHistory historyFor(String contactPublicKeyHex) {
+    return _cache[contactPublicKeyHex] ??
+        ContactPathHistory.empty(contactPublicKeyHex);
+  }
+
+  ContactPathHistory _historyFor(String contactPublicKeyHex) {
+    return _cache.putIfAbsent(
+      contactPublicKeyHex,
+      () => ContactPathHistory.empty(contactPublicKeyHex),
+    );
+  }
+
+  Future<void> _saveHistory(
+    String contactPublicKeyHex,
+    ContactPathHistory history,
+  ) async {
+    _cache[contactPublicKeyHex] = history;
+    final prefs = await SharedPreferences.getInstance();
+    final payload = <String, dynamic>{};
+    for (final entry in _cache.entries) {
+      payload[entry.key] = entry.value.toJson();
+    }
+    await prefs.setString(_storageKey, jsonEncode(payload));
+  }
+
+  List<PathRecord> _upsertDirectPath(
+    List<PathRecord> existing,
+    PathRecord updatedRecord,
+  ) {
+    final updated = List<PathRecord>.from(existing)
+      ..removeWhere((record) => record.signature == updatedRecord.signature)
+      ..insert(0, updatedRecord);
+    if (updated.length > _maxDirectPaths) {
+      return updated.take(_maxDirectPaths).toList();
+    }
+    return updated;
+  }
+
+  int _comparePathRecords(PathRecord a, PathRecord b) {
+    final successRateCompare = b.successRate.compareTo(a.successRate);
+    if (successRateCompare != 0) return successRateCompare;
+
+    final successCountCompare = b.successCount.compareTo(a.successCount);
+    if (successCountCompare != 0) return successCountCompare;
+
+    final aRtt = a.lastRoundTripTimeMs == 0 ? 1 << 30 : a.lastRoundTripTimeMs;
+    final bRtt = b.lastRoundTripTimeMs == 0 ? 1 << 30 : b.lastRoundTripTimeMs;
+    final rttCompare = aRtt.compareTo(bRtt);
+    if (rttCompare != 0) return rttCompare;
+
+    return b.lastUsedAt.compareTo(a.lastUsedAt);
+  }
+
+  PathRecord? _findDirectPath(List<PathRecord> records, String signature) {
+    for (final record in records) {
+      if (record.signature == signature) {
+        return record;
+      }
+    }
+    return null;
+  }
+
+  String _signature(Uint8List bytes) =>
+      bytes.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join();
+}

lib/services/route_hash_preferences.dart

@@ -0,0 +1,26 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+class RouteHashPreferences {
+  static const String _hashSizeKey = 'route_hash_size';
+  static const int defaultHashSize = 1;
+
+  static Future<int> getHashSize() async {
+    final prefs = await SharedPreferences.getInstance();
+    final value = prefs.getInt(_hashSizeKey) ?? defaultHashSize;
+    return _normalize(value);
+  }
+
+  static Future<void> setHashSize(int value) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setInt(_hashSizeKey, _normalize(value));
+  }
+
+  static int normalizeSync(int value) => _normalize(value);
+
+  static int _normalize(int value) {
+    if (value < 1 || value > 3) {
+      return defaultHashSize;
+    }
+    return value;
+  }
+}

lib/services/tile_cache_service.dart

@@ -1,284 +0,0 @@
-import 'package:flutter/foundation.dart';
-import 'package:flutter_map/flutter_map.dart';
-import 'package:flutter_map_tile_caching/flutter_map_tile_caching.dart';
-import 'package:vector_map_tiles_mbtiles/vector_map_tiles_mbtiles.dart';
-import 'package:mbtiles/mbtiles.dart';
-import '../models/map_layer.dart';
-
-class TileCacheService {
-  static const String _storeName = 'meshcore_sar_tiles';
-
-  // Global flag to ensure ObjectBox is only initialized once
-  static bool _objectBoxInitialized = false;
-  static final _initLock = <String, Future<void>>{};
-
-  late final FMTCStore _store;
-  bool _isInitialized = false;
-  bool _isDownloading = false;
-
-  Future<void> initialize() async {
-    if (_isInitialized) return;
-
-    // Ensure we only initialize ObjectBox once globally
-    if (!_objectBoxInitialized) {
-      // Use a lock to prevent concurrent initialization attempts
-      final initFuture = _initLock.putIfAbsent('objectbox', () async {
-        try {
-          await FMTCObjectBoxBackend().initialise();
-          _objectBoxInitialized = true;
-        } catch (e) {
-          // Already initialized or error - that's okay
-          _objectBoxInitialized = true;
-        }
-      });
-      await initFuture;
-    }
-
-    try {
-      _store = FMTCStore(_storeName);
-      await _store.manage.create();
-      _isInitialized = true;
-    } catch (e) {
-      // Store might already exist
-      _store = FMTCStore(_storeName);
-      _isInitialized = true;
-    }
-  }
-
-  FMTCTileProvider getTileProvider(MapLayer layer) {
-    if (!_isInitialized) {
-      throw StateError(
-        'TileCacheService not initialized. Call initialize() first.',
-      );
-    }
-    return FMTCTileProvider(
-      stores: {_storeName: BrowseStoreStrategy.readUpdateCreate},
-      loadingStrategy: BrowseLoadingStrategy.cacheFirst,
-      cachedValidDuration: const Duration(days: 30),
-    );
-  }
-
-  /// Get tile provider for WMS layers with caching support
-  /// WMS layers require special handling because they use WMSTileLayerOptions
-  FMTCTileProvider getTileProviderForWms(MapLayer layer) {
-    if (!_isInitialized) {
-      throw StateError(
-        'TileCacheService not initialized. Call initialize() first.',
-      );
-    }
-    if (!layer.isWms) {
-      throw ArgumentError('Layer must be a WMS layer');
-    }
-
-    // Return the same cached tile provider
-    // The WMS URL construction is handled by flutter_map's WMSTileLayerOptions
-    return FMTCTileProvider(
-      stores: {_storeName: BrowseStoreStrategy.readUpdateCreate},
-      loadingStrategy: BrowseLoadingStrategy.cacheFirst,
-      cachedValidDuration: const Duration(days: 30),
-    );
-  }
-
-  Future<void> downloadRegion({
-    required MapLayer layer,
-    required LatLngBounds bounds,
-    required int minZoom,
-    required int maxZoom,
-    Function(double progress)? onProgress,
-  }) async {
-    if (!_isInitialized) {
-      throw StateError(
-        'TileCacheService not initialized. Call initialize() first.',
-      );
-    }
-
-    if (_isDownloading) {
-      throw StateError('A download is already in progress. Cancel it first.');
-    }
-
-    _isDownloading = true;
-
-    try {
-      final region = RectangleRegion(bounds);
-
-      final downloadable = region.toDownloadable(
-        minZoom: minZoom,
-        maxZoom: maxZoom,
-        options: TileLayer(urlTemplate: layer.urlTemplate),
-      );
-
-      final download = _store.download.startForeground(region: downloadable);
-
-      await for (final progress in download.downloadProgress) {
-        if (onProgress != null && progress.maxTilesCount > 0) {
-          // Use attemptedTilesCount instead of successfulTilesCount
-          // attemptedTilesCount includes successful + buffered + skipped tiles
-          final percentage = progress.percentageProgress;
-          debugPrint(
-            'Download progress: ${progress.attemptedTilesCount}/${progress.maxTilesCount} = ${percentage.toStringAsFixed(1)}% (successful: ${progress.successfulTilesCount}, buffered: ${progress.bufferedTilesCount}, skipped: ${progress.skippedTilesCount})',
-          );
-          onProgress(percentage);
-        }
-      }
-    } finally {
-      _isDownloading = false;
-    }
-  }
-
-  Future<void> cancelDownload() async {
-    if (!_isInitialized) return;
-    await _store.download.cancel();
-  }
-
-  Future<void> clearCache() async {
-    if (!_isInitialized) return;
-    await _store.manage.delete();
-    await _store.manage.create();
-  }
-
-  Future<int> getCachedTileCount() async {
-    if (!_isInitialized) return 0;
-    final stats = await _store.stats.length;
-    return stats;
-  }
-
-  Future<double> getCacheSizeMB() async {
-    if (!_isInitialized) return 0.0;
-    final stats = await _store.stats.size;
-    return stats / (1024 * 1024);
-  }
-
-  Future<List<String>> getAvailableStores() async {
-    if (!_isInitialized) {
-      throw StateError(
-        'TileCacheService not initialized. Call initialize() first.',
-      );
-    }
-
-    final stores = await FMTCRoot.stats.storesAvailable;
-    return stores.map((store) => store.storeName).toList();
-  }
-
-  Future<Map<String, dynamic>> getStoreStats() async {
-    if (!_isInitialized) return {};
-
-    final length = await _store.stats.length;
-    final size = await _store.stats.all.then((a) => a.size);
-
-    return {
-      'tileCount': length,
-      'sizeMB': size / 1024,
-      'storeName': _storeName,
-    };
-  }
-
-  /// Get vector tile provider for MBTiles layers
-  MbTilesVectorTileProvider? getVectorTileProvider(MapLayer layer) {
-    if (!layer.isVector || layer.mbtilesFile == null) {
-      return null;
-    }
-
-    try {
-      final mbtiles = MbTiles(
-        mbtilesPath: layer.mbtilesFile!.path,
-        gzip: layer.isGzipped ?? false,
-      );
-
-      return MbTilesVectorTileProvider(
-        mbtiles: mbtiles,
-      );
-    } catch (e) {
-      debugPrint('Error creating vector tile provider: $e');
-      return null;
-    }
-  }
-
-  /// Export the current tile cache store to an archive file
-  ///
-  /// [outputPath] - Full path where the archive should be saved (e.g., '/path/to/export.fmtc')
-  ///
-  /// Returns the number of tiles exported
-  Future<int> exportStore(String outputPath) async {
-    if (!_isInitialized) {
-      throw StateError(
-        'TileCacheService not initialized. Call initialize() first.',
-      );
-    }
-
-    try {
-      final external = FMTCRoot.external(pathToArchive: outputPath);
-      final result = await external.export(storeNames: [_storeName]);
-
-      debugPrint('Export completed: $result tiles exported to $outputPath');
-      return result;
-    } catch (e) {
-      debugPrint('Error exporting store: $e');
-      rethrow;
-    }
-  }
-
-  /// Import a tile cache store from an archive file
-  ///
-  /// [filePath] - Path to the .fmtc archive file to import
-  /// [storeNames] - Optional list of store names to import (null = import all)
-  /// [strategy] - Conflict resolution strategy (default: merge)
-  ///
-  /// Returns a map with import statistics (e.g., tile count, stores imported)
-  Future<Map<String, dynamic>> importStore(
-    String filePath, {
-    List<String>? storeNames,
-    ImportConflictStrategy strategy = ImportConflictStrategy.merge,
-  }) async {
-    if (!_isInitialized) {
-      throw StateError(
-        'TileCacheService not initialized. Call initialize() first.',
-      );
-    }
-
-    try {
-      final external = FMTCRoot.external(pathToArchive: filePath);
-      final result = external.import(storeNames: storeNames, strategy: strategy);
-
-      // Wait for the import to complete and get tile count
-      final tileCount = await result.complete;
-
-      // Wait for store states
-      final storesToStates = await result.storesToStates;
-
-      debugPrint('Import completed: $tileCount tiles imported, ${storesToStates.length} stores');
-
-      // Count successful stores (those that weren't skipped)
-      final successfulCount = storesToStates.values.where((state) => state.name != null).length;
-
-      return {
-        'successfulStores': successfulCount,
-        'tileCount': tileCount,
-        'storesToStates': storesToStates,
-      };
-    } catch (e) {
-      debugPrint('Error importing store: $e');
-      rethrow;
-    }
-  }
-
-  /// List all stores available in an archive file without importing
-  ///
-  /// [filePath] - Path to the .fmtc archive file to inspect
-  ///
-  /// Returns a list of store names contained in the archive
-  Future<List<String>> listArchiveStores(String filePath) async {
-    try {
-      final external = FMTCRoot.external(pathToArchive: filePath);
-      final stores = await external.listStores;
-      debugPrint('Archive contains ${stores.length} stores: $stores');
-      return stores;
-    } catch (e) {
-      debugPrint('Error listing archive stores: $e');
-      rethrow;
-    }
-  }
-
-  void dispose() {
-    _isInitialized = false;
-  }
-}

lib/services/voice_recorder_service.dart

@@ -18,7 +18,7 @@ class VoiceRecorderService {
 
   /// Request microphone permission.  Returns true if granted.
   Future<bool> requestPermission() async {
-    return _recorder.hasPermission();
+    return _recorder.hasPermission(request: true);
   }
 
   /// Start capturing PCM audio.
@@ -38,9 +38,7 @@ class VoiceRecorderService {
       throw StateError('VoiceRecorderService: already recording');
     }
 
-    _controller = StreamController<Int16List>(
-      onCancel: () => _stopInternal(),
-    );
+    _controller = StreamController<Int16List>(onCancel: () => _stopInternal());
     _isRecording = true;
 
     _startRecording(
@@ -167,17 +165,17 @@ class _VoiceDynamicsProcessor {
     required int sampleRate,
     required bool enableCompressor,
     required bool enableLimiter,
-  })  : _enableCompressor = enableCompressor,
-        _enableLimiter = enableLimiter,
-        _compressor = _SimpleCompressor(
-          sampleRate: sampleRate.toDouble(),
-          thresholdDb: -18.0,
-          ratio: 2.5,
-          attackMs: 8.0,
-          releaseMs: 120.0,
-          makeupGainDb: 4.0,
-        ),
-        _limiter = _PeakLimiter(ceilingDb: -1.0);
+  }) : _enableCompressor = enableCompressor,
+       _enableLimiter = enableLimiter,
+       _compressor = _SimpleCompressor(
+         sampleRate: sampleRate.toDouble(),
+         thresholdDb: -18.0,
+         ratio: 2.5,
+         attackMs: 8.0,
+         releaseMs: 120.0,
+         makeupGainDb: 4.0,
+       ),
+       _limiter = _PeakLimiter(ceilingDb: -1.0);
 
   Int16List process(Int16List input) {
     final output = Int16List(input.length);
@@ -214,11 +212,11 @@ class _SimpleCompressor {
     required double attackMs,
     required double releaseMs,
     required double makeupGainDb,
-  })  : _thresholdDb = thresholdDb,
-        _ratio = ratio,
-        _makeupGain = math.pow(10.0, makeupGainDb / 20.0).toDouble(),
-        _attackCoeff = math.exp(-1.0 / (sampleRate * (attackMs / 1000.0))),
-        _releaseCoeff = math.exp(-1.0 / (sampleRate * (releaseMs / 1000.0)));
+  }) : _thresholdDb = thresholdDb,
+       _ratio = ratio,
+       _makeupGain = math.pow(10.0, makeupGainDb / 20.0).toDouble(),
+       _attackCoeff = math.exp(-1.0 / (sampleRate * (attackMs / 1000.0))),
+       _releaseCoeff = math.exp(-1.0 / (sampleRate * (releaseMs / 1000.0)));
 
   double process(double x) {
     final absX = x.abs();
@@ -266,14 +264,14 @@ class _VoiceBandPassFilter {
     required int sampleRate,
     required double lowCutHz,
     required double highCutHz,
-  })  : _highPass = _BiquadFilter.highPass(
-          sampleRate: sampleRate.toDouble(),
-          cutoffHz: lowCutHz,
-        ),
-        _lowPass = _BiquadFilter.lowPass(
-          sampleRate: sampleRate.toDouble(),
-          cutoffHz: highCutHz,
-        );
+  }) : _highPass = _BiquadFilter.highPass(
+         sampleRate: sampleRate.toDouble(),
+         cutoffHz: lowCutHz,
+       ),
+       _lowPass = _BiquadFilter.lowPass(
+         sampleRate: sampleRate.toDouble(),
+         cutoffHz: highCutHz,
+       );
 
   Int16List process(Int16List input) {
     final output = Int16List(input.length);
@@ -306,11 +304,11 @@ class _BiquadFilter {
     required double b2,
     required double a1,
     required double a2,
-  })  : _b0 = b0,
-        _b1 = b1,
-        _b2 = b2,
-        _a1 = a1,
-        _a2 = a2;
+  }) : _b0 = b0,
+       _b1 = b1,
+       _b2 = b2,
+       _a1 = a1,
+       _a2 = a2;
 
   factory _BiquadFilter.lowPass({
     required double sampleRate,

lib/utils/avatar_label_helper.dart

@@ -0,0 +1,39 @@
+class AvatarLabelHelper {
+  static final RegExp _alnumChunks = RegExp(r'[A-Za-z0-9]+');
+
+  static String buildLabel(String name) {
+    final trimmed = name.trim();
+    if (trimmed.isEmpty) return '?';
+
+    if (trimmed.startsWith('#')) {
+      final hashBody = trimmed.substring(1).replaceAll(RegExp(r'[\s_-]+'), '');
+      if (hashBody.isEmpty) {
+        return '#';
+      }
+      return '#${_take(hashBody, 2)}'.toUpperCase();
+    }
+
+    final parts = _alnumChunks
+        .allMatches(trimmed)
+        .map((match) => match.group(0)!)
+        .where((part) => part.isNotEmpty)
+        .toList();
+
+    if (parts.isEmpty) {
+      return '?';
+    }
+
+    if (parts.length >= 2) {
+      final first = _take(parts[0], 1);
+      final second = _take(parts[1], 1);
+      return '$first$second'.toUpperCase();
+    }
+
+    return _take(parts.first, 2).toUpperCase();
+  }
+
+  static String _take(String value, int count) {
+    if (value.length <= count) return value;
+    return value.substring(0, count);
+  }
+}

lib/utils/contact_grouping.dart

@@ -0,0 +1,116 @@
+import '../models/contact.dart';
+
+class InferredContactGroup {
+  final String key;
+  final String label;
+  final List<Contact> contacts;
+
+  const InferredContactGroup({
+    required this.key,
+    required this.label,
+    required this.contacts,
+  });
+
+  DateTime get latestSeen => contacts.first.lastSeenTime;
+}
+
+class ContactListItem {
+  final Contact? contact;
+  final InferredContactGroup? group;
+
+  const ContactListItem._({this.contact, this.group});
+
+  const ContactListItem.contact(Contact contact) : this._(contact: contact);
+
+  const ContactListItem.group(InferredContactGroup group)
+    : this._(group: group);
+
+  bool get isGroup => group != null;
+
+  DateTime get latestSeen => group?.latestSeen ?? contact!.lastSeenTime;
+}
+
+class ContactGrouping {
+  static final RegExp _prefixedNamePattern = RegExp(
+    r'^([A-Za-z0-9]{2,})([-_/:])',
+  );
+
+  static List<Contact> sortByLastSeen(List<Contact> contacts) {
+    return List<Contact>.from(contacts)
+      ..sort((a, b) => b.lastSeenTime.compareTo(a.lastSeenTime));
+  }
+
+  static List<ContactListItem> buildItems(
+    List<Contact> contacts, {
+    int minGroupSize = 4,
+  }) {
+    final sortedContacts = sortByLastSeen(contacts);
+    return buildItemsFromSorted(sortedContacts, minGroupSize: minGroupSize);
+  }
+
+  static List<ContactListItem> buildItemsFromSorted(
+    List<Contact> sortedContacts, {
+    int minGroupSize = 4,
+  }) {
+    final groupedContacts = <String, List<Contact>>{};
+    final groupLabels = <String, String>{};
+
+    for (final contact in sortedContacts) {
+      final prefix = _extractPrefix(contact.displayName);
+      if (prefix == null) continue;
+      groupedContacts.putIfAbsent(prefix.key, () => <Contact>[]).add(contact);
+      groupLabels.putIfAbsent(prefix.key, () => prefix.label);
+    }
+
+    final eligibleGroups = <String, InferredContactGroup>{};
+    for (final entry in groupedContacts.entries) {
+      if (entry.value.length < minGroupSize) continue;
+      eligibleGroups[entry.key] = InferredContactGroup(
+        key: entry.key,
+        label: groupLabels[entry.key] ?? entry.key,
+        contacts: entry.value,
+      );
+    }
+
+    final emittedGroups = <String>{};
+    final items = <ContactListItem>[];
+
+    for (final contact in sortedContacts) {
+      final prefix = _extractPrefix(contact.displayName);
+      final group = prefix == null ? null : eligibleGroups[prefix.key];
+      if (group == null) {
+        items.add(ContactListItem.contact(contact));
+        continue;
+      }
+      if (emittedGroups.add(group.key)) {
+        items.add(ContactListItem.group(group));
+      }
+    }
+
+    return items;
+  }
+
+  static _GroupPrefix? _extractPrefix(String name) {
+    final trimmed = name.trim();
+    if (trimmed.isEmpty) return null;
+
+    final match = _prefixedNamePattern.firstMatch(trimmed);
+    if (match == null) return null;
+
+    final rawPrefix = match.group(1);
+    final separator = match.group(2);
+    if (rawPrefix == null || separator == null) return null;
+
+    return _GroupPrefix(
+      key: rawPrefix.toUpperCase(),
+      label: '$rawPrefix$separator',
+    );
+  }
+}
+
+class _GroupPrefix {
+  final String key;
+  final String label;
+
+  const _GroupPrefix({required this.key, required this.label});
+}

lib/utils/fast_gps_packet.dart

@@ -0,0 +1,69 @@
+import 'dart:typed_data';
+
+class FastGpsPacket {
+  static const int magic = 0x47; // 'G'
+  static const int _payloadLength = 19;
+  // Store coordinates in microdegrees. This preserves sub-meter precision,
+  // which comfortably satisfies the meter-accuracy requirement.
+  static const double coordinateScale = 1e6;
+
+  final String senderKey6;
+  final double latitude;
+  final double longitude;
+  final int timestampSeconds;
+
+  const FastGpsPacket({
+    required this.senderKey6,
+    required this.latitude,
+    required this.longitude,
+    required this.timestampSeconds,
+  });
+
+  static bool isFastGpsBinary(Uint8List payload) =>
+      payload.length == _payloadLength && payload[0] == magic;
+
+  static FastGpsPacket? tryParseBinary(Uint8List payload) {
+    if (!isFastGpsBinary(payload)) return null;
+
+    final key6 = payload
+        .sublist(1, 7)
+        .map((b) => b.toRadixString(16).padLeft(2, '0'))
+        .join();
+    final data = ByteData.sublistView(payload);
+    final latitude = data.getInt32(7, Endian.little) / coordinateScale;
+    final longitude = data.getInt32(11, Endian.little) / coordinateScale;
+    final timestampSeconds = data.getUint32(15, Endian.little);
+
+    if (!_isValidCoordinate(latitude, longitude)) {
+      return null;
+    }
+
+    return FastGpsPacket(
+      senderKey6: key6,
+      latitude: latitude,
+      longitude: longitude,
+      timestampSeconds: timestampSeconds,
+    );
+  }
+
+  Uint8List encodeBinary() {
+    final out = Uint8List(_payloadLength);
+    final data = ByteData.sublistView(out);
+    out[0] = magic;
+    for (var i = 0; i < 6; i++) {
+      out[1 + i] = int.parse(senderKey6.substring(i * 2, i * 2 + 2), radix: 16);
+    }
+    data.setInt32(7, (latitude * coordinateScale).round(), Endian.little);
+    data.setInt32(11, (longitude * coordinateScale).round(), Endian.little);
+    data.setUint32(15, timestampSeconds, Endian.little);
+    return out;
+  }
+
+  static bool _isValidCoordinate(double latitude, double longitude) {
+    if (!latitude.isFinite || !longitude.isFinite) return false;
+    return latitude >= -90.0 &&
+        latitude <= 90.0 &&
+        longitude >= -180.0 &&
+        longitude <= 180.0;
+  }
+}

lib/utils/image_message_parser.dart

@@ -4,7 +4,7 @@ const int _maxCompanionFrameBytes = 172; // MeshCore MAX_FRAME_SIZE
 const int _cmdSendRawDataOverheadBytes = 2; // cmd + pathLen
 const int _maxMeshPacketPayloadBytes = 184; // MeshCore MAX_PACKET_PAYLOAD
 const int _meshPacketHeaderBytes = 2; // mesh header bytes before path/payload
-const int _imagePacketHeaderBytes = 8; // image packet binary header in payload
+const int _imagePacketHeaderBytes = 6; // image packet binary header in payload
 const int _defaultLoRaSf = 10; // MeshCore companion defaults (SF10)
 const int _defaultLoRaCr = 5; // MeshCore companion defaults (4/5)
 const int _defaultLoRaBwHz = 250000; // MeshCore companion defaults (250kHz)
@@ -31,7 +31,7 @@ enum ImageFormat {
 /// A single binary fragment of a compressed image.
 ///
 /// Binary format (direct contacts, via pushRawData / cmdSendRawData):
-///   [0x49 'I'][sessionId:4B][fmt:1B][idx:1B][total:1B][imageData...]
+///   [0x49 'I'][sessionId:4B][idx:1B][imageData...]
 ///
 /// Legacy default is 152 data bytes per fragment.
 class ImagePacket {
@@ -50,7 +50,7 @@ class ImagePacket {
   });
 
   static const int _magic = 0x49; // 'I'
-  static const int _headerLen = 8; // magic(1)+session(4)+fmt(1)+idx(1)+total(1)
+  static const int _headerLen = 6; // magic(1)+session(4)+idx(1)
   static const int maxDataBytes =
       152; // Conservative default for compatibility.
 
@@ -65,16 +65,14 @@ class ImagePacket {
           .sublist(1, 5)
           .map((b) => b.toRadixString(16).padLeft(2, '0'))
           .join();
-      final fmtId = payload[5];
-      final index = payload[6];
-      final total = payload[7];
-      if (total < 1) return null;
+      final index = payload[5];
+      final data = payload.sublist(_headerLen);
       return ImagePacket(
         sessionId: sessionId,
-        format: ImageFormat.fromId(fmtId),
+        format: ImageFormat.avif,
         index: index,
-        total: total,
-        data: payload.sublist(_headerLen),
+        total: 0,
+        data: data,
       );
     } catch (_) {
       return null;
@@ -92,16 +90,16 @@ class ImagePacket {
     final out = Uint8List(_headerLen + data.length);
     out[0] = _magic;
     out.setRange(1, 5, sessionBytes);
-    out[5] = format.id;
-    out[6] = index;
-    out[7] = total;
+    out[5] = index;
     out.setRange(_headerLen, out.length, data);
     return out;
   }
 
   @override
-  String toString() =>
-      'ImagePacket($sessionId ${format.label} [$index/${total - 1}] ${data.length}B)';
+  String toString() {
+    final suffix = total > 0 ? ' ${format.label} [$index/${total - 1}]' : ' [$index]';
+    return 'ImagePacket($sessionId$suffix ${data.length}B)';
+  }
 }
 
 /// Compute the maximum safe image data bytes for a direct route path.
@@ -125,7 +123,10 @@ int safeImageDataBytesForPath(int pathLen) {
       ? maxRawPayloadFromCommandFrame
       : maxRawPayloadFromMesh;
   final maxData = maxRawPayload - ImagePacket._headerLen;
-  return maxData.clamp(1, 255).toInt();
+  // Keep a safety margin below the theoretical direct-route ceiling.
+  // Fragments at the absolute 172-byte command-frame limit have proven flaky
+  // in practice, so cap to the conservative protocol default.
+  return maxData.clamp(1, ImagePacket.maxDataBytes).toInt();
 }
 
 /// Approximate end-to-end transmit time for image fragments on MeshCore LoRa.
@@ -243,11 +244,11 @@ int _resolveBandwidthHz(int? rawBw) {
 /// Envelope announcing image availability (control plane).
 ///
 /// Text format:
-///   IE1:{sid}:{fmt}:{total}:{w}:{h}:{bytes}:{senderKey6}:{ts}:{ver}
+///   IE4:{sid}:{fmt}:{total}:{w}:{h}:{bytes}
 /// Example:
-///   IE1:deadbeef:0:7:128:128:1050:aabbccddeeff:1700000000:1
+///   IE4:deadbeef:0:7:3k:3k:t6
 class ImageEnvelope {
-  static const String prefix = 'IE1:';
+  static const String _prefixV4 = 'IE4:';
 
   final String sessionId; // 8 hex chars
   final ImageFormat format;
@@ -255,8 +256,6 @@ class ImageEnvelope {
   final int width;
   final int height;
   final int sizeBytes; // total compressed image size
-  final String senderKey6; // 12 hex chars (6 bytes)
-  final int timestampSec;
   final int version;
 
   const ImageEnvelope({
@@ -266,48 +265,38 @@ class ImageEnvelope {
     required this.width,
     required this.height,
     required this.sizeBytes,
-    required this.senderKey6,
-    required this.timestampSec,
-    this.version = 1,
+    this.version = 4,
   });
 
-  static bool isEnvelope(String text) => text.startsWith(prefix);
+  static bool isEnvelope(String text) => text.startsWith(_prefixV4);
 
   static ImageEnvelope? tryParse(String text) {
     if (!isEnvelope(text)) return null;
-    final body = text.substring(prefix.length);
+    final body = text.substring(_prefixV4.length);
     final parts = body.split(':');
-    if (parts.length != 9) return null;
+    if (parts.length != 6) return null;
     try {
-      final sid = parts[0];
-      final fmtId = int.tryParse(parts[1]);
-      final total = int.tryParse(parts[2]);
-      final w = int.tryParse(parts[3]);
-      final h = int.tryParse(parts[4]);
-      final bytes = int.tryParse(parts[5]);
-      final senderKey6 = parts[6];
-      final ts = int.tryParse(parts[7]);
-      final ver = int.tryParse(parts[8]);
+      final sid = _decodeSessionId(parts[0]);
+      final fmtId = _parseInt(parts[1], base36: true);
+      final total = _parseInt(parts[2], base36: true);
+      final w = _parseInt(parts[3], base36: true);
+      final h = _parseInt(parts[4], base36: true);
+      final bytes = _parseInt(parts[5], base36: true);
 
-      if (!RegExp(r'^[0-9a-fA-F]{8}$').hasMatch(sid)) return null;
+      if (sid == null) return null;
       if (fmtId == null) return null;
       if (total == null || total < 1 || total > 255) return null;
       if (w == null || h == null || w < 1 || h < 1) return null;
       if (bytes == null || bytes < 1) return null;
-      if (!RegExp(r'^[0-9a-fA-F]{12}$').hasMatch(senderKey6)) return null;
-      if (ts == null || ts <= 0) return null;
-      if (ver == null || ver != 1) return null;
 
       return ImageEnvelope(
-        sessionId: sid.toLowerCase(),
+        sessionId: sid,
         format: ImageFormat.fromId(fmtId),
         total: total,
         width: w,
         height: h,
         sizeBytes: bytes,
-        senderKey6: senderKey6.toLowerCase(),
-        timestampSec: ts,
-        version: ver,
+        version: 4,
       );
     } catch (_) {
       return null;
@@ -315,23 +304,25 @@ class ImageEnvelope {
   }
 
   String encode() =>
-      '$prefix${sessionId.toLowerCase()}:${format.id}:$total:$width:$height:$sizeBytes:${senderKey6.toLowerCase()}:$timestampSec:$version';
+      '$_prefixV4${_encodeSessionId(sessionId)}:'
+      '${_toBase36(format.id)}:${_toBase36(total)}:${_toBase36(width)}:'
+      '${_toBase36(height)}:${_toBase36(sizeBytes)}';
 }
 
 /// Direct request to fetch image fragments (control plane).
 ///
 /// Text format:
-///   IR1:{sid}:{want}:{requesterKey6}:{ts}:{ver}
+///   IR4:{sid}:{want}:{requesterKey6}
 /// Example:
-///   IR1:deadbeef:a:aabbccddeeff:1700000010:1
+///   IR4:deadbeef:a:aabbccddeeff
 class ImageFetchRequest {
-  static const String prefix = 'IR1:';
+  static const String _prefixV4 = 'IR4:';
+  static const int _binaryMagic = 0x69; // 'i'
 
   final String sessionId;
   final String want; // 'all' or 'missing'
   final List<int> missingIndices;
   final String requesterKey6; // 12 hex chars
-  final int timestampSec;
   final int version;
 
   const ImageFetchRequest({
@@ -339,52 +330,78 @@ class ImageFetchRequest {
     this.want = 'all',
     this.missingIndices = const [],
     required this.requesterKey6,
-    required this.timestampSec,
-    this.version = 1,
+    this.version = 4,
   });
 
-  static bool isRequest(String text) => text.startsWith(prefix);
+  static bool isRequest(String text) => text.startsWith(_prefixV4);
+  static bool isRequestBinary(Uint8List payload) =>
+      payload.isNotEmpty && payload[0] == _binaryMagic;
 
   static ImageFetchRequest? tryParse(String text) {
     if (!isRequest(text)) return null;
-    final body = text.substring(prefix.length);
+    final body = text.substring(_prefixV4.length);
     final parts = body.split(':');
-    if (parts.length != 5) return null;
+    if (parts.length != 3) return null;
     try {
-      final sid = parts[0];
+      final sid = _decodeSessionId(parts[0]);
       final wantToken = parts[1];
       final requesterKey6 = parts[2];
-      final ts = int.tryParse(parts[3]);
-      final ver = int.tryParse(parts[4]);
       final normalizedWant = wantToken == 'a'
           ? 'all'
-          : (wantToken.startsWith('m-') ? 'missing' : wantToken);
+          : ((wantToken.startsWith('m')) ? 'missing' : wantToken);
 
-      if (!RegExp(r'^[0-9a-fA-F]{8}$').hasMatch(sid)) return null;
+      if (sid == null) return null;
       final missingIndices = <int>[];
       if (normalizedWant == 'missing') {
-        final encoded = wantToken.substring(2);
+        final encoded = wantToken.substring(1);
         if (encoded.isEmpty) return null;
-        for (final raw in encoded.split(',')) {
-          final idx = int.tryParse(raw);
-          if (idx == null || idx < 0 || idx > 254) return null;
-          missingIndices.add(idx);
-        }
+        missingIndices.addAll(_decodeMissingIndicesCompact(encoded));
         if (missingIndices.isEmpty) return null;
       } else if (normalizedWant != 'all') {
         return null;
       }
       if (!RegExp(r'^[0-9a-fA-F]{12}$').hasMatch(requesterKey6)) return null;
-      if (ts == null || ts <= 0) return null;
-      if (ver == null || ver != 1) return null;
 
       return ImageFetchRequest(
-        sessionId: sid.toLowerCase(),
+        sessionId: sid,
         want: normalizedWant,
         missingIndices: missingIndices,
         requesterKey6: requesterKey6.toLowerCase(),
-        timestampSec: ts,
-        version: ver,
+        version: 4,
+      );
+    } catch (_) {
+      return null;
+    }
+  }
+
+  static ImageFetchRequest? tryParseBinary(Uint8List payload) {
+    if (!isRequestBinary(payload)) return null;
+    if (payload.length < 13) return null; // magic+sid+flags+key6+count
+    try {
+      final sid = payload
+          .sublist(1, 5)
+          .map((b) => b.toRadixString(16).padLeft(2, '0'))
+          .join()
+          .toLowerCase();
+      final flags = payload[5];
+      final requesterKey6 = payload
+          .sublist(6, 12)
+          .map((b) => b.toRadixString(16).padLeft(2, '0'))
+          .join()
+          .toLowerCase();
+      final missingCount = payload[12];
+      if (payload.length != 13 + missingCount) return null;
+      final wantMissing = (flags & 0x01) == 0x01;
+      final missing = <int>[];
+      for (var i = 0; i < missingCount; i++) {
+        missing.add(payload[13 + i]);
+      }
+      return ImageFetchRequest(
+        sessionId: sid,
+        want: wantMissing ? 'missing' : 'all',
+        missingIndices: missing,
+        requesterKey6: requesterKey6,
+        version: 4,
       );
     } catch (_) {
       return null;
@@ -393,10 +410,167 @@ class ImageFetchRequest {
 
   String encode() {
     final wantToken = want == 'missing' && missingIndices.isNotEmpty
-        ? 'm-${missingIndices.join(',')}'
+        ? 'm${_encodeMissingIndicesCompact(missingIndices)}'
         : (want == 'all' ? 'a' : want);
-    return '$prefix${sessionId.toLowerCase()}:$wantToken:${requesterKey6.toLowerCase()}:$timestampSec:$version';
+    return '$_prefixV4${_encodeSessionId(sessionId)}:$wantToken:${requesterKey6.toLowerCase()}';
   }
+
+  Uint8List encodeBinary() {
+    if (!RegExp(r'^[0-9a-fA-F]{8}$').hasMatch(sessionId)) {
+      throw ArgumentError.value(sessionId, 'sessionId', 'Expected 8 hex chars');
+    }
+    if (!RegExp(r'^[0-9a-fA-F]{12}$').hasMatch(requesterKey6)) {
+      throw ArgumentError.value(
+        requesterKey6,
+        'requesterKey6',
+        'Expected 12 hex chars',
+      );
+    }
+    final useMissing = want == 'missing' && missingIndices.isNotEmpty;
+    final missing = useMissing
+        ? missingIndices.where((v) => v >= 0 && v <= 254).toList()
+        : <int>[];
+
+    final out = Uint8List(13 + missing.length);
+    out[0] = _binaryMagic;
+    for (var i = 0; i < 4; i++) {
+      out[1 + i] = int.parse(sessionId.substring(i * 2, i * 2 + 2), radix: 16);
+    }
+    out[5] = useMissing ? 0x01 : 0x00;
+    for (var i = 0; i < 6; i++) {
+      out[6 + i] = int.parse(
+        requesterKey6.substring(i * 2, i * 2 + 2),
+        radix: 16,
+      );
+    }
+    out[12] = missing.length;
+    for (var i = 0; i < missing.length; i++) {
+      out[13 + i] = missing[i];
+    }
+    return out;
+  }
+}
+
+/// Per-fragment ACK for raw image payload packets.
+///
+/// Binary format:
+///   [0x6a 'j'][sessionId:4B][index:1B]
+class ImageFragmentAck {
+  static const int _binaryMagic = 0x6a; // 'j'
+
+  final String sessionId; // 8 hex chars
+  final int index; // 0..254
+
+  const ImageFragmentAck({required this.sessionId, required this.index});
+
+  static bool isImageFragmentAckBinary(Uint8List payload) =>
+      payload.length == 6 && payload[0] == _binaryMagic;
+
+  static ImageFragmentAck? tryParseBinary(Uint8List payload) {
+    if (!isImageFragmentAckBinary(payload)) return null;
+    try {
+      final sid = payload
+          .sublist(1, 5)
+          .map((b) => b.toRadixString(16).padLeft(2, '0'))
+          .join()
+          .toLowerCase();
+      final idx = payload[5];
+      return ImageFragmentAck(sessionId: sid, index: idx);
+    } catch (_) {
+      return null;
+    }
+  }
+
+  Uint8List encodeBinary() {
+    if (!RegExp(r'^[0-9a-fA-F]{8}$').hasMatch(sessionId)) {
+      throw ArgumentError.value(sessionId, 'sessionId', 'Expected 8 hex chars');
+    }
+    if (index < 0 || index > 254) {
+      throw ArgumentError.value(index, 'index', 'Expected 0..254');
+    }
+    final out = Uint8List(6);
+    out[0] = _binaryMagic;
+    for (var i = 0; i < 4; i++) {
+      out[1 + i] = int.parse(sessionId.substring(i * 2, i * 2 + 2), radix: 16);
+    }
+    out[5] = index;
+    return out;
+  }
+}
+
+int? _parseInt(String token, {required bool base36}) =>
+    int.tryParse(token, radix: base36 ? 36 : 10);
+
+String _toBase36(int value) => value.toRadixString(36);
+
+String _encodeSessionId(String sessionIdHex) {
+  if (!RegExp(r'^[0-9a-fA-F]{8}$').hasMatch(sessionIdHex)) {
+    throw ArgumentError.value(
+      sessionIdHex,
+      'sessionIdHex',
+      'Expected 8 hex chars',
+    );
+  }
+  final value = int.parse(sessionIdHex, radix: 16);
+  return value.toRadixString(36);
+}
+
+String? _decodeSessionId(String token) {
+  if (!RegExp(r'^[0-9a-z]{1,7}$').hasMatch(token)) return null;
+  final value = int.tryParse(token, radix: 36);
+  if (value == null || value < 0 || value > 0xFFFFFFFF) return null;
+  return value.toRadixString(16).padLeft(8, '0');
+}
+
+String _encodeMissingIndicesCompact(List<int> indices) {
+  final sorted = indices.where((v) => v >= 0 && v <= 254).toSet().toList()
+    ..sort();
+  if (sorted.isEmpty) return '';
+  final chunks = <String>[];
+  var start = sorted.first;
+  var prev = sorted.first;
+  for (var i = 1; i < sorted.length; i++) {
+    final curr = sorted[i];
+    if (curr == prev + 1) {
+      prev = curr;
+      continue;
+    }
+    chunks.add(
+      start == prev
+          ? _toBase36(start)
+          : '${_toBase36(start)}-${_toBase36(prev)}',
+    );
+    start = curr;
+    prev = curr;
+  }
+  chunks.add(
+    start == prev ? _toBase36(start) : '${_toBase36(start)}-${_toBase36(prev)}',
+  );
+  return chunks.join('.');
+}
+
+List<int> _decodeMissingIndicesCompact(String encoded) {
+  final out = <int>[];
+  for (final token in encoded.split('.')) {
+    if (token.isEmpty) continue;
+    if (!token.contains('-')) {
+      final value = int.tryParse(token, radix: 36);
+      if (value == null || value < 0 || value > 254) return const [];
+      out.add(value);
+      continue;
+    }
+    final parts = token.split('-');
+    if (parts.length != 2) return const [];
+    final start = int.tryParse(parts[0], radix: 36);
+    final end = int.tryParse(parts[1], radix: 36);
+    if (start == null || end == null || start < 0 || end > 254 || start > end) {
+      return const [];
+    }
+    for (var i = start; i <= end; i++) {
+      out.add(i);
+    }
+  }
+  return out;
 }
 
 /// Fragment the compressed image bytes into [ImagePacket] list.