vui is our on-device voice AI for iPhone — type or talk, and it answers out loud in a natural voice. No cloud, no account required for speech, nothing leaves your phone.
Free during beta · iPhone with iOS 26+ · ~1.2 GB one-time model download
Real voices, on your phone
vui speaks with natural, expressive voices — hesitations, breaths and all — rendered by a 300M-parameter model running entirely on the iPhone GPU.
Talk to it
Hold the mic, speak, and get a spoken reply. Speech recognition, the language model and the voice all run on-device.
Private by construction
Your words and audio never leave the phone. There is no server doing the thinking — the models are downloaded once and everything runs locally.
Works offline
On a plane, on the tube, off-grid — once the models are downloaded, vui needs no connection at all.
Request access with your Apple ID email — the invite goes out straight away.
Apple emails you a TestFlight invite. Install TestFlight from the App Store and accept it.
Open vui and download the voice model (~1.2 GB, best on Wi‑Fi). Then talk.
Feedback lands right in TestFlight (screenshot + comment), or come tell us in Discord.