Cipher Mobile

End-to-end encrypted messenger for Android — mobile companion to Cipher desktop.

Same protocol, same privacy contract, same 7-day max server retention. Built on Expo / React Native.

Status

🚧 Scaffolding incoming — this repo is currently a placeholder. The mobile app is Phase 3 of the Cipher roadmap.

Once scaffolding lands, the app will:

• Authenticate via QR-based vault bridge (Eidolon Connect) or password-sealed quick-unlock
• Open conversations and exchange messages with Cipher desktop users
• Reuse Double Ratchet sessions established cross-platform
• Honor the same privacy contract (no PII server-side, ciphertext-only relay, 7-day TTL)

Stack

• Expo SDK 52 — managed workflow, Expo Router for file-based routing
• React Native — single codebase, Android first, iOS to follow alongside the Apple Developer subscription
• cipher-e2ee — shared E2EE primitives consumed by desktop and mobile alike (no copy-paste port, no protocol drift)
• expo-secure-store — HSM-backed credential storage
• MMKV — encrypted local cache (Zustand persistence layer)
• react-native-libsodium — native bindings for the same libsodium operations as desktop
• Native WebSocket — direct connection to the bridge backend, no Socket.IO layer

Companion projects

• Oykdo/cipher — Desktop messenger (Electron / React) — alpha shipping
• Oykdo/cipher-e2ee — Shared E2EE primitives package
• Oykdo/cipher-mobile — This repo

License

MIT