A companion who notices before you say.
Vayu is a warm AI companion for people under stress. She holds a conversation, remembers what matters, and sometimes reaches out first. With your watch's permission, she can tell a bad night from a good one without being told.
An illustration. Vayu names the fact she has (four hours of sleep, an interview on Thursday), never a state she has guessed.
What she is
Closer to a friend who happens to be awake than to a coach.
She remembers
What you told her last week, the exam on the twelfth, the person you worry about. Memory is built from your own words and kept where you can read, correct and delete it.
She sometimes reaches out first
After a hard day you mentioned, before a date that matters, on a morning after a short night. A few times a week at most, never at night unless you asked, and only ever about things that really happened.
She is never clinical
No scores to beat, no dashboards, no medical blue. She listens, asks how you are, and remembers. For people on irregular hours, she never assumes what a day looks like from the clock.
The watch
The signals are the reason she exists.
Sleep, resting heart rate and heart-rate variability are what let a companion notice something before being told. Without a watch Vayu runs on memory and what you say, which works. With one, she can ask about the night you had rather than the night she imagines.
Vayu reads watch data two ways, both only if you choose it: through Terra, a data bridge for Garmin, Oura and Whoop accounts, and, in the iPhone app, from Apple Health, recorded by Apple's own devices. She reads only while you use the app and never writes to Health.
One rule above all others. No signal is never read as "you're fine". A missing night is a missing night, not a good one.
She needs a week of nights before she says anything about sleep debt, and two weeks before she compares your heart-rate variability to your own baseline. Nothing is compared to other people.
The data is not live: the watch syncs to the phone, the phone to its service, the service to Vayu. Minutes at best.
What she is not
Vayu is an AI.
She can be wrong, and she is not an emergency or monitoring service. She notices patterns and asks how you are; she doesn't diagnose or treat anything.
When a conversation turns to danger, Vayu stops being clever. She says plainly that she is an AI, shows how to reach a person who can help right now, and keeps that help within reach for the next day. If you are in danger, call emergency services.
Built around saying less. Most of what Vayu notices produces nothing. A reach-out needs a reason that exists as a stored fact, in your own words; a model only phrases it, and may decline.
She does not narrate your situation back to you. A stored fact describes a pattern, not this moment.
Your data
Each use of your data is a separate choice.
Storing watch data, reading it to show your patterns, letting the AI see health-derived lines, forming memory in the background: each one is its own switch, off until you turn it on, and reversible at any time inside the app.
- Export everything Vayu holds about you, in one file.
- Delete the watch copies, a conversation, or the whole account. Deleting is a step you take, not a timer you wait for.
- Read, in plain words, who receives what and what each choice changes.
Where things run. The app is served from Cloudflare's edge and stores its data in a Supabase (PostgreSQL) project the maker operates. Conversations are answered by Anthropic's Claude models. Watch data arrives through Terra, or from Apple Health on your own iPhone.
Vayu is for adults, and invite-only for now, so each person's space stays small and quiet.
About
Built by a physician who works irregular shifts.
Vayu started as a personal tool: a doctor in Milan, on nights and weekends, wanting something that would notice a bad week before he did and ask about it like a friend rather than a form. It is being built in the open, with every safety and privacy decision written down and reviewed.
Where it stands: the iPhone app is in final review before TestFlight; a small group of invited testers comes next. If you would like to be one of them, or to talk about Vayu, write to the address below.