This page is for people in Washington State, under its My Health My Data Act. Our privacy policy covers the rest.
Who we are
Stack is run by Dad with Style OÜ, Sepapaja tn 6, Tallinn 15551, Estonia (registry code 14696867). Write to [email protected] about anything on this page.
The health data we collect
Your weigh-ins, body measurements and progress photos.
Your workouts and sets, how you slept, and the days you were sick.
Your answers about your health: conditions, medication and old injuries.
Your food diary and your calorie and nutrient targets.
From Apple Health, only what you allow on Apple’s own screen: daily steps, active energy, walking and running distance, workouts, body weight, sleep time, resting heart rate and heart rate variability.
For coached clients: your coach’s notes about you, and call notes from your coaching calls. For clients of Founder Athlete OS, also your call transcripts, your WhatsApp messages with your coach, and your answers on the booking form.
Why we collect it
To give you what you asked Stack for: your progress, your targets, the suggestions on your Brief, and coaching if you have a coach. To keep Stack working: backups, error reports and the automated checks described in our privacy policy. We collect it only for these, or with your consent. We never sell it and never use it for ads by others. Founder Athlete OS publishes a client’s result only with that client’s written permission, never with Apple Health data.
Where it comes from
You, when you enter it in the app.
Apple Health on your iPhone, if you allow it.
Your coach, if you have one: their notes and your call notes.
The app itself, which works out your targets and suggestions from what you entered.
Who receives it
Your coach, if you have one. No coach can see a subscriber’s data.
Companies that run Stack for us: Supabase (stores it), Cloudflare (delivers the app and keeps our backups), Anthropic (reads food photos and sentences, and the problem reports you send, under a data processing agreement), and GitHub (runs our scheduled jobs, with your data passing through). If your coach records calls, your coach’s privacy notice says how. For clients of Founder Athlete OS, also those named in its privacy notice.
An AI you connect yourself, at your direction: only if you do it in Settings, then Connect your AI, and from Apple Health only your weight and steps, while Apple Health in your AI is on in Settings, then Privacy.
We have no affiliates that receive it. If you allow analytics, PostHog receives that you logged a workout, sleep or a weigh-in, never your figures. Our email service (Resend) receives no health data.
Your rights
Know and get a copy: whether we hold your health data, a copy of it, and a list of every company that received it, with a way to contact them.
Delete it: in the app, Settings, then Privacy, then Delete my account, or by writing to us. We delete it from Stack, and backup copies are gone within 14 days. For clients of Founder Athlete OS, its coaching records in Stack are kept as its privacy notice says, and deleted on request. What a coach keeps outside Stack is the coach’s to delete, and we do that for Founder Athlete OS on request.
Withdraw consent: delete the data or your account; turn off AI reading, Apple Health in your AI, call notes and your steps in them in the app under Settings, then Privacy; turn off Apple Health in the Health app (Settings, then Apps, then Health, then Stack); remove Stack from your AI’s connectors, or write to us, to end your AI connection.
Write to [email protected]. We answer within 45 days. If we need longer, we tell you why within those 45 days, and take at most 45 more. Using a right never changes the price or what Stack does for you.
If we say no, you can appeal by replying to our answer with the word “appeal”. We answer the appeal within 45 days. If we still say no, you can complain to the Washington State Attorney General at atg.wa.gov.
Changes
When this page changes, the date at the top changes. If we want to use your health data for something new or share it with someone new, we ask you first.