Your data
Privacy Policy
Last updated: 28 October 2026
In short: your journal lives on your phone. It only reaches our server if you turn on backup, and it only reaches an AI provider if you allow AI writing. We never sell your data, show ads or put what you write into analytics.
Who we are
SisterStars (“we”) is responsible for the personal data described here. Contact us any time at [email protected].
What stays on your phone
Your intentions, signs, notes, rituals, challenges and kept texts are stored in a database on your device. Without backup, none of it leaves your phone.
What we process on our server
- Your account. SisterStars creates an anonymous account so your phone can talk to our server. If you sign in with Apple or Google, we store the identifier they give us for your account. We do not store your name, and we do not need your email address.
- Backup (only if you turn it on). Your journal is copied to our server so it survives a new phone or a reinstall and syncs between your devices. Turning backup off deletes the server copy.
- Your subscription. Apple or Google handle payment. We receive the purchase details (product, dates, status) to unlock the app; we never see your card details.
- AI writing (only if you allow it). When you ask for a script, affirmations or a weekly summary, the request goes through our server to the AI provider named in the app before you agree. Weekly summaries use counts only (for example, how many signs you logged), never what you wrote. We keep the text the AI produced and a fingerprint (hash) of your request, not the request itself, to limit usage and avoid writing the same summary twice.
- Technical logs. Our server logs requests (time, address, result) for security and troubleshooting.
Analytics
Only if you allow it, we measure how the app is used (for example, which screens are opened) with PostHog, hosted in the EU. Free text you write is never part of these events. You can change this any time in Settings → Privacy.
Where your data is
Our server runs in Hungary (EU). Traffic reaches it through Cloudflare, which protects the connection. The AI provider may process requests outside the EU; the app names the provider and asks for your consent before the first request, and you can withdraw it in Settings → Privacy.
Legal basis
We process data to provide the app and your subscription (contract), and for backup, AI writing and analytics on the basis of your consent, which you can withdraw at any time. Server logs rely on our legitimate interest in keeping the service secure.
How long we keep it
- Account, backup and AI records: until you turn backup off (backup) or delete your account (everything).
- Server backups: overwritten within 14 days.
- Purchase records: as long as the law requires for accounting.
Your choices and rights
In the app, Settings → Privacy lets you turn backup, analytics and AI on or off, and Settings → Account lets you sign out or delete your account. Deleting your account removes your data from our server and, for Sign in with Apple, revokes the link with Apple. Deleting the app does not cancel a subscription; cancel it in the App Store or Google Play.
You can ask us for a copy of your data, to correct or delete it, or to restrict or object to its processing, by writing to [email protected]. You can also complain to your local data protection authority (in Hungary: NAIH, naih.hu).
Age
SisterStars is for people aged 16 and over.
Changes
If this policy changes in a way that matters, we will tell you in the app before it applies.