Use your phone as a webcam. The phone app streams its camera to the Lenny desktop app over Wi-Fi, and the desktop app is where you pick the camera, resolution, frame rate, focus and exposure.
Early and in progress. The core is Rust now (ADR-0006) and the new desktop app is a Rust app, built and tested on Linux first (ADR-0007; screenshots below, from the build sandbox with a synthetic phone). Windows moves to the same app next; until then the Windows desktop is the Flutter one.
What works today, on Android → Windows (Flutter desktop):
- Live H.264 stream over Wi-Fi, around 100 ms end to end on a home network.
- Pairing: scan the QR code on the PC, tap Find PCs, or type the address. Phones you allowed once reconnect without asking.
- Remote camera control from the PC: lens (0.6× / 1× / 2× / front), tap to focus, focus lock, exposure and exposure lock, torch.
- Aspect, resolution (720p / 1080p / 4K) and frame rate, switched live.
- Phone battery level on the PC, Connect / Disconnect on both sides.
Not there yet:
- Virtual camera for Discord, Teams, Zoom, browsers (the main goal; next milestone).
- OBS plugin.
- iOS phone app and Linux desktop app (designed for, not built). macOS is out of scope.
- USB connection, encryption.
- Virtual camera on Windows (plan in architecture §7.3–7.4): shared-memory frame buffer + DirectShow / Media Foundation camera.
- OBS plugin.
- Desktop at the default 1600×900 window: the Exposure card scrolls and some stat values get cut off. Make it fit.
- 60 fps (needs Camera2 high-speed session on some phones), on-phone preview, settings screen, bundle fonts offline.
Testing notes live in docs/testing.md. The wire protocol is at 1.1 (protocol.md §11).
Grab the Android APK and the Windows zip from the Releases page, when there is one. Otherwise build it:
- Install the phone app and open Lenny Desktop on the PC. Both must be on the same Wi-Fi.
- On the phone, tap Scan QR and point it at the code on the PC (or Find PCs).
- The first time, allow the phone on the PC.
Windows may ask to let Lenny through the firewall: allow it on private networks, or the phone can't find the PC.
Needs Flutter (stable), Android Studio (SDK + NDK), Rust (stable) with the Android targets and cargo-ndk, and, for Windows, Visual Studio 2022 with the C++ workload.
rustup target add aarch64-linux-android armv7-linux-androideabi x86_64-linux-android i686-linux-android
cargo install cargo-ndkcd app
flutter build apk --release # app/build/app/outputs/flutter-apk/app-release.apk
flutter build windows --release # app/build/windows/x64/runner/Release/ (ship the whole folder)Core library tests (Rust; the Android build runs cargo-ndk for you):
cargo test --workspace
core/tools/abi_check.sh # the Rust core still exports exactly include/lenny/lenny.h (needs cbindgen, clang)Linux desktop (Rust):
cargo run --release -p lenny_desktop # the app; falls back to a null virtual camera without v4l2loopback
sudo modprobe v4l2loopback exclusive_caps=1 card_label=Lenny # for a real /dev/videoN other apps can open
cargo run -p lenny_desktop --example fake_phone -- 127.0.0.1 47474 # no phone at hand| Part | What |
|---|---|
core/ |
Rust library shared by every platform: protocol, sessions, pairing, clock sync. C ABI (include/lenny/lenny.h). |
vcam/ |
Virtual camera behind one trait: v4l2loopback on Linux, a null (file) backend anywhere. |
desktop/ |
Rust desktop app (egui): Linux now, Windows next. |
app/ |
Flutter app, one codebase: phone UI on Android, desktop UI on Windows. |
plugins/android_camera |
Camera2 capture + MediaCodec H.264 encoder (Kotlin + JNI). |
plugins/windows_receiver |
Media Foundation decoder + preview texture (C++). |
More: architecture, wire protocol, design system, testing.