Privacy Policy
This policy explains what Tall-O collects, why we collect it, and who we share it with. Tall-O is the mobile app and the website at onetallo.com.
1. What we collect
Account data
- Your email address and your name.
- Your password, stored only as a cryptographic hash. We never store the password itself.
- If you sign in with Google or TikTok: the provider's account identifier and display name.
Growth profile
- Date of birth and sex.
- Your height, and the heights you enter for your mother and father.
- Activity level, flexibility, and typical sleep duration.
- Your preferred units.
Activity you record
- Height measurements over time.
- Completed tasks, meals and food entries, water intake, and sleep entries.
- Posts, comments, and likes in the community area.
- Messages you send to the AI coach, and a short summary of past conversations.
Technical data
- A session token that keeps you signed in.
- IP address and device user agent, recorded with the session.
- Subscription status, if you buy Tall-O Pro.
Website
If you join the waitlist, we store your email address, the country that Cloudflare reports for your request, and the page that referred you. We do not store your IP address in the waitlist table.
2. Why we collect it
- To calculate your height projection. This needs your age, sex, height, and your parents' heights.
- To show your progress over time.
- To let the AI coach answer questions about your own data.
- To keep you signed in and to secure your account.
- To operate subscriptions.
- To understand which features people use, so we can improve the app.
3. The AI coach
The coach sends your message and relevant parts of your own Tall-O data to Anthropic, which generates the reply. The coach can read only your own account. It cannot read another user's data. We do not use your messages to train any model.
4. Who we share data with
We use these service providers. Each one receives only the data it needs.
- Anthropic — generates AI coach replies.
- PostHog — product analytics.
- AppsFlyer — measures which advert or link led to an install.
- RevenueCat — manages subscriptions.
- Resend — sends account emails, such as password reset codes.
- Google and TikTok — sign-in, if you choose them.
- Railway — hosts the application server and database.
- Cloudflare — hosts this website and the waitlist.
We do not sell your data. We do not share your data with advertisers for their own purposes.
5. Young people
Tall-O is for people who are still growing, so many users are young. You must be at least 13 years old to create an account. If the law where you live sets a higher age for data consent, you need permission from a parent or guardian below that age.
If you are a parent or guardian and you believe your child created an account without your permission, email [email protected]. We will delete the account and its data.
6. Your choices and rights
- See your data. The app shows your profile and every entry you record.
- Correct your data. Edit your profile in Settings.
- Delete your data. Use Settings → Reset all data.
- Delete your account. Email [email protected]. We delete the account and its data.
- Disconnect a provider. Use Settings → Connected accounts. You cannot remove your only sign-in method.
If you live in the European Economic Area or the United Kingdom, you also have the right to object to processing, to restrict processing, to data portability, and to complain to your data protection authority.
7. How long we keep data
We keep your account data until you delete your account. Password reset codes expire after 15 minutes. Session tokens expire on their own schedule. Waitlist entries stay until you ask us to remove them.
8. Security
We store passwords only as hashes. Traffic between the app and our server uses HTTPS. Sign-in tokens from Google are verified against Google's public keys before we trust them. No system is perfectly secure, so we cannot promise absolute security.
9. Changes to this policy
We update this page when our practices change. The date at the top shows the current version.
10. Contact
Email [email protected] with any question about this policy or your data.
Tall-O offers lifestyle guidance informed by publicly available growth research. It is not medical advice, and is not affiliated with or endorsed by the CDC. Talk to a doctor about any concern with your growth or health.