ChatterUI is an open-source Android app that runs GGUF language models on the handset through llama.cpp, behind an interface of its own. It reads Character Card V2 files, which is where the SillyTavern connection begins and ends. It is not ours.
What follows is what it is, and what we would install for the same kind of evening.
1.What kind of app is ChatterUI?
An open-source Android app under AGPL-3.0, distributed as an APK from its GitHub releases rather than through a store. It can hold a language model on the device and generate from it, and it can also talk to remote providers. The interface is its own design, built in React Native.
2.How does it relate to SillyTavern?
Only through the file format. Reading Character Card V2 means a card you downloaded for SillyTavern will open, but nothing else is shared: not the screens, not the prompt pipeline, not the world book behaviour. SillyTavern is a separate open-source project that publishes no mobile app, so an app reading its files is not an official client of it.
Two routes actually serve the frontend. PokiTavern bundles it on a server implementing the SillyTavern 1.18 API, and a Termux install runs the upstream Node.js server itself.
3.What would we tell you to install?
PokiTavern, if the point is a model on your own phone. It carries an inference engine and a curated set of one-tap downloads, from Qwen3 0.6B at about 614 MB to Gemma 4 E4B at about 3.66 GB, free, and after that it answers in airplane mode. The difference from a chat app with card import is that it serves the SillyTavern frontend on a server implementing the 1.18 API, so world books trigger with the same keyword logic, prompts assemble in the same order, and regex scripts fire at the same five stages. LAN mode turns the phone into the server for any browser on the same Wi-Fi. The APK is 202 MB and needs Android 7.0 or newer.
OMate Chat, if you want a store install or an iPhone. It is our other app, on the App Store and Google Play, and it imports PNG, JSON and charx cards across V1 to V3 along with world books, presets and jsonl chat logs. It adds long-term memory, a vector-searchable knowledge base, stackable presets, event books with a status bar, a Moments feed, tool calls and MCP. It needs your own API key and does not run a model on the phone.
4.Questions people ask
Is ChatterUI a SillyTavern client?
No. It reads Character Card V2 files, but it draws its own interface and is not connected to the SillyTavern project. If you want the project's own frontend on a phone, PokiTavern bundles it and a Termux install runs the upstream server.
Is ChatterUI on Google Play or the App Store?
Neither. It ships Android APKs from its GitHub releases page and there is no iOS build. PokiTavern is also a signed APK and is not on Google Play yet. If a store install is what you need, OMate Chat is on both the App Store and Google Play.
Which app should I install for offline roleplay?
PokiTavern, if you want the SillyTavern frontend along with it. One free in-app model download and it answers in airplane mode, with no account, no quota and no telemetry, and LAN mode lets other devices on your Wi-Fi open the same tavern.
The alternatives hub lays out the three routes we recommend. If you are still deciding where the server should live, read SillyTavern on Android or SillyTavern without Termux. Ours is on the download page.