A private AI companion that knows you. It remembers your life, runs entirely on your iPhone, and belongs to you alone. Offline. Private. Yours.
A companion that remembers.
Tell it about your day, your people, what you're working through, and it actually remembers, conversation after conversation. No re-explaining yourself.
A private place to think.
Talk through what’s on your mind, out loud, with no one listening. Your words never leave your phone, so you can be honest.
Yours, not the cloud's.
Everything TAU knows about you lives on your device, in a memory you can see and edit. Delete anything, anytime.
Cloud AI forgets you between chats, and sends everything you say to a server. Assistants answer questions but never build a real memory of you. Companion apps remember, but they're built to keep you hooked.
TAU remembers you like a companion, runs entirely on your device like almost nothing else does, and is built to be honest with you, never to maximize your screen time.
The AI lives on your phone.
Qwen3-4B, an open-source model, runs fully on-device. After a one-time download, no servers and no internet required.
It builds a memory of you.
As you talk, TAU quietly forms a private memory of what matters to you, stored locally.
You see and control everything.
Open the Memories screen anytime to read, edit, or delete what TAU knows. Nothing hidden.
Nothing leaves unless you choose.
Your conversations and memory stay on your device, by default, always.
Built to make you more capable, not more dependent.
TAU works for you, and only you.
Early looks at the app. The Memories screen is visible, editable, and yours. That is what makes TAU different.
$0forever
TAU remembers what matters.
The companion, on-device and offline, with a focused memory.
$9.99per month
or $59.99 a year
TAU remembers more of your life.
Longer history, a better use of memory, and the features still to come.
Coming to iPhone 15 Pro and the iPhone 16 and 17 lineups. Any iPhone with 8GB of memory.
Qwen3-4B, an open-source language model. It downloads to your iPhone on first launch, then runs entirely on the device. Nothing you say is sent out for inference.
After that first download, yes. Chat, memory, and the model all live on your phone. No connection required.
The model is about 2.3 GB. That is a one-time download of the model files. Your conversations are never part of it.
iPhone 15 Pro and later, including the iPhone 16 and 17 lineups. Any iPhone with 8 GB of memory.
No. Conversations and memories stay in the app's private storage on your device. We cannot read, recover, or hand them over, because we do not have them.
Uninstalling TAU erases the local database, including its memory of you. We cannot restore it. Deleting your account from Settings does the same, and also removes your account from our servers.
Free: TAU remembers what matters, with a focused memory, at $0. Pro: TAU remembers more of your life, with a longer history and a better use of memory. New features land in Pro. $9.99 a month or $59.99 a year, billed by Apple.
Three language models trained from scratch. They are not what the app runs today: that is Qwen3-4B. They are here to be studied, built for a kind of on-device efficiency a full Transformer does not have, and a possible next runtime for TAU. Read the notes
TAU ships on iPhone soon. Follow along while it gets there, or leave an email and we will tell you the day it goes live.
