Have you ever wanted to watch a foreign YouTube video, a live stream on Twitch, or a show on Netflix without constantly staring at subtitles?
To solve this, I built ALAD Mobile (Live Audio Dubbing) — an open-source native Android application that captures internal system audio in real-time, streams it through Google's Gemini Multimodal Live API, and instantly plays back the translated voice over any active media.
ALAD Mobile creates a system-wide floating overlay widget that sits comfortably over your active applications. Once activated:
Building low-latency real-time voice translation on mobile required a carefully structured stack:
StateFlow
, and SharedFlow
MediaProjection
/ AudioRecord
for internal audio capture + `AudioTrack`
for low-latency playback`TYPE_APPLICATION_OVERLAY`
Using Android's `MediaProjection`
API and AudioRecord
, the app captures raw PCM audio streams from the device's internal sound engine without relying on external microphone input.
Traditional REST API requests introduce too much latency for live translation. ALAD Mobile opens a persistent WebSocket connection directly to Gemini's Live API, continuously streaming PCM audio chunks in real-time.
As Gemini processes and translates the stream, incoming audio payloads are decoded and pushed directly into a low-latency AudioTrack
buffer for smooth, near-instant voice playback.
To ensure zero friction, a Floating Control Widget built with Android's System Alert Window lets users control dubbing and switch target languages seamlessly over any running app.
StateFlow
.ALAD Mobile is 100% Free and Open Source. It runs using a free API key directly from Google AI Studio — no subscriptions or user accounts required.
If you find this project interesting, feel free to drop a ⭐ star on GitHub, submit a PR, or leave your architectural feedback below!