Files
tether/android
Patrick Ecord d1750a95d6 core: account-derived rooms — same account → same room everywhere
Add room_for_account(account) = sha256(account)[..4] hex, exported via UniFFI so
every client derives the IDENTICAL room from a shared identity. Clients now
default their room to the account-derived id (falling back to a device id only
when signed out). With the prefilled account, all our devices land in one room
across LAN, the relay, and RTC — so "just us" works cross-network, not only on
the same Wi-Fi. The single canonical Rust impl guarantees the ids match across
Swift/Kotlin/agent (a hand-rolled per-platform hash would risk drift).

Verified: agent and the live Mac app both derive room 360309c8 from
"pecord@gmail.com"; the Mac app publishes there on the public relay.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-21 01:55:28 -05:00
..

tether — Android client

Compose UI over the shared tethercore Rust engine (SSE + RTC) via UniFFI Kotlin bindings. Same engine as the iOS/macOS apps and the desktop agent; only the UI and the binding language differ.

Build (requires the Android NDK)

This machine had no Android toolchain when the app was scaffolded, so the native .so and Kotlin bindings are not committed — they're generated:

  1. Install the toolchain:
    • Android Studio (SDK + NDK), or sdkmanager "ndk;26.x"
    • cargo install cargo-ndk
    • rustup target add aarch64-linux-android x86_64-linux-android
    • export ANDROID_NDK_HOME=/path/to/ndk
  2. Generate native libs + bindings:
    ../core/build-android.sh
    
    This places libtethercore.so under app/src/main/jniLibs/<abi>/ and the Kotlin binding under app/src/main/java/uniffi/tethercore/.
  3. Build/run the app: open android/ in Android Studio (it generates the Gradle wrapper on first sync), then Run. From the CLI, generate the wrapper once with gradle wrapper, then ./gradlew :app:assembleDebug.

Notes

  • Default server is http://10.0.2.2:8765 — the emulator's alias for the host machine's localhost. On a physical device use the relay's LAN address.
  • Android (unlike iOS) lets a foreground app observe clipboard changes, so the app auto-sends via OnPrimaryClipChangedListener. A foreground Service would extend that to the background (future work).
  • The room id is a per-install UUID (RoomIdentity); account-derived shared rooms are future work, matching the iOS plan.