Mesh over Bluetooth LE, TCP, or Reticulum
Source: Hacker News
Columba
Columba is a simple messaging and voice app for the Reticulum network on Android.
It lets you send LXMF messages and make LXST voice calls without relying on the internet, cell towers, or any central servers.
Built with a native Android interface and Material Design 3, Columba brings mesh networking to your pocket in a familiar, easy‑to‑use package.
Screenshots
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| Chat interface | Voice call interface |
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| App settings |
(All images are hosted on GitHub and will load automatically.)
What You Can Do
- Message without infrastructure – Send messages even when the internet is down or unavailable.
- Connect in multiple ways – Use Bluetooth LE for nearby peers, Wi‑Fi at home, LoRa radio via RNode for long‑range links, or TCP to any Reticulum server worldwide.
- Stay private – End‑to‑end encryption with no accounts, no tracking, and no central servers.
- Share location – Securely share your location with others; view it on a dedicated map.
- Download maps for offline use – Import or download MBTiles map files (vector or raster).
- Build your network – Relay traffic for others and expand the mesh.
- Keep your identity – Generate your messaging identity directly on your device.
- Manage multiple identities – Switch easily between several identities.
- Export and import identities – Back up your keys externally or migrate to a new device. Import from other Reticulum clients such as Sideband.
- Share your identity via QR code – Built‑in QR‑code scanner and generator for quick identity exchange.
- Custom colour themes – Not a fan of the default palette? Customize colours to your heart’s content!
Getting Started
Download the latest release from the Releases page and install it on your Android device. For APK verification instructions, see SECURITY.md.
Install via Obtainium
Alternative download (NomadNet)
You can also fetch the APK through NomadNet:
8d1788fdb4e9f85303cfdf7481e721c7:/page/index.muAbout Reticulum
Reticulum is a networking stack that lets devices communicate directly with each other, forming resilient mesh networks. It is optimized for low‑bandwidth, high‑latency connections and can operate over almost any medium.
Columba uses:
- LXMF (Lightweight Extensible Message Format) to send messages across the Reticulum network.
- A native Android implementation of ble‑reticulum to enable messaging over BLE with other Android and Linux devices.
Want to learn more? Visit the official Reticulum documentation.
Why “Columba”
Columba, Latin for “dove,” is a constellation in the southern sky that depicts a dove. Doves are commonly a symbol of peace and hope and have been used as messengers throughout history.