Offline voice (Moonshine)

Offline Moonshine is an English dictation engine that runs entirely on your phone, with Moonshine Tiny, a 27-million-parameter model made for short phrases on small devices. Once the model is downloaded, no audio leaves the phone. While a layout in another language is in use, dictation uses the system recognizer instead.

Setting it up

WM Keyboard › Voice typing

Choose Offline Moonshine under Recognition engine, then download the model from the Moonshine model group that appears below it: 151 MB in three files, from Hugging Face at a fixed revision, each checked against its published SHA-256.

How it works

Moonshine transcribes a phrase once you stop, and a phrase can run to 30 seconds. Where Whisper always pads what you said to a 30-second window, Moonshine reads only as much audio as there is, so a three-second phrase costs a three-second encode, which is what makes it quick on a phone. The text arrives punctuated and capitalised, then goes through the same spacing, spoken punctuation and undo as any other dictation (see Voice typing).

Moonshine, Asr4All or Whisper

For English, Asr4All shows the words while you speak, and the whisper.cpp Whisper models take your own words as hints and run to two minutes. Moonshine is the small, quick one: the least to download among them for its accuracy, and the fastest to answer a short phrase.

Details & edge cases

No words to listen for. Moonshine has no way to take a list of names or terms, so Words to listen for does not show while it is the engine.

Both editions. The runtime, ExecuTorch built for the keyboard’s models alone, is in full and lite alike. A build made without it, as F-Droid’s is, does not offer the engine.

The licence. Moonshine is Useful Sensors’ model, under the MIT licence; it is credited in the app’s About screen.