Offline speech toolkit using onnxruntime for speech recognition, text-to-speech, VAD, diarization and more, across many platforms and languages.
15.4K1.8KC++Apache-2.0Updated yesterday
niedev/RTranslator
Offline real-time speech translation app for Android that connects users over Bluetooth LE for multi-person conversations.
Open-source alternative to:Google Translate
- Stars
- 10,529
- Forks
- 951
- Open issues
- 27
- Last commit
- yesterday
What is it?
RTranslator is an Android app that translates speech and text in real time. In Conversation mode, two or more users with the app connect over Bluetooth LE; each person's speech is transcribed on their phone, sent to the others as text, translated locally, and read aloud through the speaker or a connected Bluetooth headset.
WalkieTalkie mode is aimed at short exchanges such as asking for directions. It works on a single phone, listens in two selected languages, detects which one is being spoken, and speaks the translation back in turns. A text translation mode covers ordinary typed translation.
Translation uses Meta's NLLB model and speech recognition uses OpenAI's Whisper, both converted to ONNX and quantized to run on the device. The app is listed as requiring at least 6GB of RAM, and the models are downloaded on first launch (about 1.2GB).
Key features
- 01Two-way speech translation between phones connected over Bluetooth LE
- 02Walkie-talkie mode that detects the spoken language across two selected languages on one phone
- 03Text translation mode
- 04Offline operation with on-device NLLB and Whisper models
- 05Supports Bluetooth headsets for input and playback
Use cases
- Having a face-to-face conversation with someone who speaks a different language
- Asking directions or talking with a shop assistant while traveling
- Translating a multi-person conversation where each participant has the app
Topics
FAQ
- What is RTranslator?
- Offline real-time speech translation app for Android that connects users over Bluetooth LE for multi-person conversations. RTranslator is an Android app that translates speech and text in real time. In Conversation mode, two or more users with the app connect over Bluetooth LE; each person's speech is transcribed on their phone, sent to the others as text, translated locally, and read aloud through the speaker or a connected Bluetooth headset.
- Is RTranslator free to use? What license does it have?
- RTranslator is open source under the Apache-2.0 license. Check the license terms before using it in commercial products.
- Is RTranslator still maintained?
- Actively maintained. The last commit to RTranslator was on Oct 20, 2026.
- What can I use RTranslator for?
- Having a face-to-face conversation with someone who speaks a different language Asking directions or talking with a shop assistant while traveling Translating a multi-person conversation where each participant has the app
- Where can I get RTranslator?
- The source code and installation instructions are on GitHub: https://github.com/niedev/RTranslator
Summary generated by AI from the project's README. GitHub stats refresh daily.
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