Columba brings mesh networking to Android with a native messaging app that works without internet or cell towers. Built for the Reticulum network, the app uses Bluetooth LE, WiFi, TCP, or LoRa radio to enable communication anywhere. With Material Design 3 interface, users can send LXMF messages and make LXST voice calls while maintaining complete privacy through end-to-end encryption.

Unlike traditional messaging apps, Columba requires no accounts, tracking, or central servers. Users generate their messaging identity directly on their device and can manage multiple identities with easy export and import capabilities. The app supports offline map downloads in MBTiles format and allows users to help relay traffic for others, expanding the mesh network. Custom color themes let users personalize their experience beyond the default appearance.

Reticulum serves as the underlying networking stack, optimized for low bandwidth and high latency connections across nearly any medium. Columba implements ble-reticulum for Bluetooth LE communication with other Android and Linux devices. The app represents a significant step toward resilient, decentralized communication infrastructure that remains functional during internet outages or in areas without cellular coverage. Available for download from GitHub releases, Columba provides APK verification instructions in its SECURITY.md file, ensuring users can safely install this privacy-focused messaging solution.