Last updated: October 5, 2026
When you create an account, we store your email address, a username, and your birth month and day (no year). We also sync your stone's data — its name, touch count and progress, and a simple daily log of what appeared on it (rain, snow, moss, flowers; never your location) — and, if you add them, your profile picture and your journal entries (text and stone snapshots), so they stay with you across devices.
We do not collect your birth year, precise location, browsing behavior, device identifiers, or any data unrelated to your stone. There are no analytics trackers, no advertising identifiers, and no third-party data brokers.
If you allow location access, your approximate location is used to show local weather on your stone; weather data comes from Apple Weather. To find stones near you, the app looks up stones in a wide area around you (about 20 km); your precise location is never sent to us. When you return a stone to nature with location on, we save roughly where it was left — shifted by 1–2 km — so someone nearby can pick it up. This location is stored with the stone, not with your account. Each stone also gets a permanent number based on the country and city where it was first found (for example, DE-BER-1); if location is off, it is numbered EARTH. The number is visible to anyone who later holds the stone, and it stays with the stone when you return it or delete your account. It never includes anything more precise than the city.
Your account data is used solely to sync your stone across your own devices. Your birth month and day are used to recognize your birthday within the app. We do not use your data for advertising, profiling, or any purpose beyond the core experience.
An Absurd Stone uses Firebase (by Google) for authentication and data sync. Firebase processes data under Google's privacy policy. You can also sign in with Apple or Google; they only share your name and email address with us, as you allow. Weather is provided by Apple Weather. No other third-party services have access to your personal data.
If you leave your email on an-absurd-stone.web.app, we store it in Firebase together with the time you signed up, your browser's user-agent string and the page that linked you to the site (if any). We use it for one thing only: a single email when An Absurd Stone launches. It is not shared, not used for marketing, and not connected to an app account. We delete the list once that email has been sent. To be removed earlier, email us at the address below.
You can delete your account at any time in Settings → Profile. Deleting your account permanently removes your account data, stone and journal from our servers. Your stone's number stays in our registry, marked as gone, with no link to you. A stone you have already returned to nature stays in nature without any link to you. You may also contact us to request deletion.
Questions about your data or this policy? Email mayujiadesign@gmail.com.