Built the end-to-end Flutter/Android app for HyperMesh — SpecFive’s off-grid mesh-messaging product that keeps teams connected with encrypted chat over BLE and Heltec LoRa nodes when there is no cellular or Wi-Fi. GorTastic is one of the companion LoRa mesh apps that combines that encrypted mesh chat with an asynchronous multiplayer game synced peer-to-peer over the mesh.
What I built:
- Mesh transport layer with a custom BLE peripheral/central plugin, UDP communication to Heltec LoRa nodes, and multi-hop relay with hop limits, message de-duplication, and per-channel routing (LoRa, BLE, or both).
- End-to-end encryption using X25519 key exchange and ChaCha20-Poly1305 authenticated encryption, with group key exchange for 1:1 and group chats.
- Offline-first Drift/SQLite persistence, a foreground service for background mesh connectivity, and send/fetch on background isolates to keep the UI responsive.
- Live crew map with GPS and offline tile caching (flutter_map, Geolocator), plus QR-based contact sharing.
- Embedded asynchronous multiplayer games whose state syncs peer-to-peer over the LoRa mesh (delivered via InAppWebView).
- Shipped SpecFive companion LoRa mesh apps on Google Play — Mesh-Tac-Toe (1K+), Mesh Chess (500+), CheckTastic (100+), and GorTastic (100+ installs).
