OpenMesh
Application · Offline chat / Android · 2026
Chat without the internet: phones connect over Bluetooth and Wi-Fi Direct and messages hop from device to device.
A mesh messenger for Android with no servers or accounts, featuring end-to-end encryption, channels, GPS position sharing and SOS alerts – for mountains, festivals and network outages.
Phones running OpenMesh find and connect to each other on their own, and each one relays messages onward, up to ten hops. Without coverage a message waits in a queue and is handed to every new neighbour, so someone walking between groups carries it along.
Private chats are encrypted with ECDH and AES-256-GCM, and every packet is signed with ECDSA. In the field there is SOS with a GPS position, an area map drawn without the internet, a radar of people nearby and an emergency torch with Morse code.
Features
- mesh network up to 10 hops
- end-to-end encryption
- SOS with GPS position and offline map
- photos and files over the mesh
- requires Android 8 or newer
Technology
- Kotlin
- Jetpack Compose
- Nearby Connections
- ECDH/ECDSA
My role
Design, architecture, implementation and releases