What is Radio Mode?
Radio mode lets you use Carroted Maps' full mapping and communication features with no internet connection, no cell service, and no Wi-Fi, in places where normal communication infrastructure doesn't exist or has failed.
How it works
Radio groups use Meshtastic or MeshCore, LoRa radio mesh networking firmware. Each person in your team connects a small radio device to their phone via Bluetooth. Those devices talk to each other over LoRa radio waves, forming a mesh network that can span miles.
When you drop a pin or send a message in a Radio group:
Carroted Maps encodes the data into a compact binary format.
Sends it to your radio device over Bluetooth.
The device broadcasts it over LoRa radio.
Nearby devices in the mesh receive and relay it (mesh = automatic repeating).
Teammates' radio devices receive the signal and pass it to their phones via Bluetooth.
Their Carroted Maps apps decode it and update the map.
The result: everyone's maps and chat stay in sync with zero internet.
Range
LoRa radio range depends heavily on terrain and obstructions:
| Environment | Typical range |
|---|---|
| Open field / flat terrain | 5–15 km (3–10 miles) |
| Rolling hills / light forest | 2–5 km |
| Dense forest / urban canyon | 0.5–2 km |
| Building to building (urban) | 100–500 m |
In a mesh, devices relay packets between nodes automatically, so total coverage can be much larger than the range between any two devices.
When to use Radio mode
- Search and rescue operations in remote areas
- Hiking or backcountry expeditions
- Disaster response when infrastructure is down
- Events in areas with poor cell coverage
- Military or security operations requiring RF-only comms
- Any situation where you want communications that don't depend on third-party infrastructure
What you need
- A LoRa radio device running Meshtastic or MeshCore firmware for each person in your team
- Bluetooth enabled on your phone
Compatible firmware
Carroted Maps supports devices running one of two LoRa mesh firmware platforms:
- Meshtastic, the most widely used LoRa mesh firmware, large open-source community
- MeshCore, an alternative mesh firmware also fully supported by Carroted Maps
Both work identically with Carroted Maps, same features, same setup flow.
Hardware
Any LoRa device with Bluetooth running Meshtastic or MeshCore firmware is compatible. A few popular options:
| Device | Notes |
|---|---|
| RAK WisMesh Tag | Compact EDC device, IP66, built-in GPS, 5–6 day battery, ships pre-flashed |
| Heltec V3 | Budget-friendly, widely available |
| LilyGO T-Beam | Built-in GPS and battery management |
| RAK WisBlock | Modular, good for custom builds |
Radio vs Online groups
| Feature | Online Group | Radio Group |
|---|---|---|
| Internet required | Yes | No |
| Real-time sync | Yes | Yes (via mesh) |
| Map pins, routes, areas | Yes | Yes |
| Text chat | Yes | Yes |
| @mention map items in chat | Yes | Yes |
| Message delivery status | Pending / Failed | Pending / Sent / Failed |
| Voice notes | Yes | No |
| Weather overlays | Yes | No |
| Live location sharing | Yes | Yes (throttled) |
| Member roles (ADMIN/MEMBER/VIEWER) | Yes | No (all users equal) |
| Push notifications | Yes | No (local alerts only) |
| Cloud backup | N/A | Optional |
| Range | Unlimited (via internet) | Limited by radio range |