LocalType details
How the keyboard behaves, what the optional models do, and what it stores.
The short version is on the LocalType page. For Chime itself, the model that provides the suggestions, see More about Chime.
Typing
- Three word suggestions, with the likeliest in the middle. Tap to complete a word or replace a selection.
- Clear typos are corrected at a word boundary using touch position. Uncertain and two-word repairs are offered for you to apply. Press delete immediately or tap Undo to restore the original. In a scripted benchmark on two Pixels, with taps scattered 14 px around each key, LocalType fixed 134 of 200 planted typos where Gboard fixed 103; with taps scattered 33 px the two were tied. Scripted taps are not human typing, and no speed advantage is claimed.
- Emoji suggestions, a full emoji grid, accented letters and IPA. Hold an emoji suggestion for variations; hold a letter and slide for accents.
- Voice input, new in 0.5.15 and still being tested. Tap the microphone key beside the emoji button and speak; tap it again, or any key, to stop. It uses Android’s on-device speech recognizer only, so it needs Android 12 or later and a phone that has one; on a Pixel that recognizer has no network permission. Dictated words are not learned or logged, and Android asks for the microphone the first time you tap the key. English only.
- Clipboard paste and Saved text. Pasted text is not learned or corrected at the next space.
- Add words, manage learned words, choose a number row and theme. Appearance → Raise the keyboard adds 16, 32 or 48 dp above navigation.
Gestures and controls
Hold space to switch keyboards. Double-tap shift for caps lock; tap space twice to end a sentence. The optional Triple-tap space to proofread setting uses a third quick tap to request a Nano/Gemma review without adding another space; it starts off. The clipboard button pastes a recent copy; hold it to save the text. The face button opens emoji; hold it for Saved text. Hold an emoji suggestion for related choices. Turn emoji suggestions off to keep three word slots. Keys support TalkBack exploration and typing.
Completions reuse an existing space. Punctuation attaches to the automatic space; pressing space after a comma keeps one separator, and Return removes the automatic space before a newline. Quotes and apostrophes attach too. Words you revisit are protected from automatic correction; new words you type afterward can be corrected again. Undo remains available briefly while preserving subsequent text.
Optional proofreading
The keyboard is complete without anything in this section: Chime needs no download, and typing, correction and suggestions use no Google service or model. For extra suggestions or sentence proofreading, LocalType can also use Gemini Nano where Google Play services makes it available, or an optional 2.4 GB Gemma 4 E2B download. Both run on the phone and both stay off until you ask. Tap the sparkle for words. Select a sentence and tap Proofread selection, or hold the sparkle to check the current sentence. Accept or dismiss the highlighted proposal; nothing is rewritten automatically.
Download and resource use
Use Extra suggestions and proofreading → Download Gemma 4 E2B in settings. Downloads use Wi-Fi unless you choose otherwise, resume after interruption and are verified before use. On GrapheneOS, allow LocalType’s Network permission first.
Gemma runs separately so the keyboard can continue if it stops. Keep Gemma ready uses about 2 GB of memory. With Chime off, Nano/Gemma can also respond after a pause; Ask Nano/Gemma only when I tap stops automatic requests. Those requests pause on Battery Saver, below 20% battery or when the phone is warm. Manual requests remain available.
The Chime model
Built in: 2.03M parameters, a 2.22 MB file and up to 63 tokens of sentence context. Chime is on by default; saved off choices are respected. Warm next-word model inference measured 3.09–3.24 ms at p95 on two Pixels; this is not end-to-end typing latency. Its weights stay fixed while LocalType learns your words separately on the phone.
From LocalType 0.5.13, a deliberate keep or suggestion choice can qualify after one use; ordinary known words need two. Personal suggestions use up to three preceding words completed here and occupy at most one strip slot. That history stays on the phone and is cleared by Forget learned words. These application changes do not change Chime’s weights or establish an advantage over another keyboard.
Try the browser demo · Write-up and shareable cards · Benchmark against Gboard · Training and measurements · Weights and model card
Your data and your choices
What you type stays on the phone: suggestions, learning, Chime and the optional language model all run there. LocalType’s own code goes online only when you ask: for the optional model download from Hugging Face, and when you tap Check for updates. Neither sends anything you type.
Typing, correction and suggestions use no Google service and no Google model. The app does include two Google libraries, ML Kit and LiteRT-LM, so that it can offer the optional Gemini Nano and Gemma features. Ordinary typing never calls them, but ML Kit starts with the app and can send Google statistics about how the Gemini Nano feature is used. Android’s own network counters on my two test phones show how little that is: apart from the Gemma download I asked for, the app made three exchanges of a few kilobytes each in the eight and five days since it was installed, the size of an update check, and none in the last three days. The counters cannot say which code made them. To rule it out, switch off LocalType’s Network permission where your phone offers that, as GrapheneOS does; typing works the same without it, and only the model download and the update check stop.
It saves words you add, which words you use after which, recent model answers and recent emoji in private app storage; Chime itself saves nothing. Misspellings are never learned. Password fields get no suggestions at all, and nothing typed in incognito fields is saved. If you turn on Keep a typing log, it also keeps what the strip suggested and the words you typed or tapped next, on the phone, until you export or clear it. Forget learned words clears all of that; text you keep in Saved text stays until you remove it.
Release files and licenses
The word list comes from FrequencyWords (OpenSubtitles 2018) under CC BY-SA 4.0. Recognized words come from SCOWL, Copyright 2000-2018 Kevin Atkinson and contributors, used under its permissive licence (notice included in the app). The optional model is Gemma 4 E2B for LiteRT-LM under Apache 2.0. On-device inference uses Google's LiteRT-LM and ML Kit.
By Luke Steuber. Android package: dev.localtype.keyboard. From 0.4.3 it is signed with a release key, certificate SHA-256 87:32:E1:75:65:9C:05:91:6D:D8:1F:CA:5D:D6:27:2F:F2:20:4C:CF:07:52:16:FB:F1:6A:89:AE:F6:66:3E:F5. Earlier previews were debug-signed.