Kotatsu: AI Companion Crew — last updated September 6, 2026
Kotatsu is a chat app with a small cast of fictional, AI-written characters. There is no account and no sign-in. This page explains exactly what leaves your phone and why.
When you send a message, the recent part of the conversation (your last messages, the characters' last replies, and a short summary the app keeps of things the crew should remember) is sent over an encrypted connection to our server, which forwards it to Google's Gemini API to generate the reply. We do not store your messages on our server after the reply is returned. Google processes the request under its API terms and does not use API data to train its models. The full conversation history lives only on your device.
To run the free tier, our server keeps a daily message count keyed to a random identifier generated by the app. It contains no name, email, phone number or device serial. Counts are deleted after 30 days.
Subscriptions are processed by Apple. Our subscription provider, RevenueCat, receives the same random identifier and your purchase status so the app can unlock Pro and restore purchases. We never receive your name, email or card details.
If you turn on check-ins, they are local notifications scheduled on your device. Nothing is sent to us to trigger them. Turn them off in Settings at any time.
If a message contains language that suggests you may be at risk of harming yourself, the app shows crisis resources (988 in the United States, findahelpline.com elsewhere). This check happens on the server as part of generating the reply and is not stored or reported anywhere.
We do not collect analytics that identify you, we do not sell or share data, we do not use your conversations for advertising, and we do not track you across apps or websites.
The crew are fictional characters written by the studio and voiced by an AI model. They are not people, not therapists and not medical professionals. Kotatsu is companionship and conversation, not treatment.
Kotatsu is rated 18+ and is intended for adults. It is not directed at children.
Questions or deletion requests: tryformaapp@gmail.com.