PRIVACY POLICY
This policy explains what information Kollatz (the website at kollatz.app and its Android app) collects, and how it's used. Kollatz is an independently run project — not part of a larger company.
What we collect
If you choose to sign in with Google, we receive and store:
- Your name and email address, as provided by your Google account
- Your Google profile picture URL (used only to display it next to your name)
- A Google account identifier, used to recognize your account on return visits
As you play, we store your gameplay data tied to your account: scores, the highest stage reached, and time played. This is what powers the leaderboard and the "resume where you left off" feature.
If you don't sign in, you can still play as a guest — no personal data is collected, but scores aren't saved between visits.
What we don't collect
Kollatz does not currently show ads, run analytics or tracking scripts, or share any data with advertising networks. We don't collect location data, contacts, photos, or anything from your device beyond what's described above.
How your data is used
Solely to run the game: identifying your account, saving your scores and progress, and displaying the leaderboard. We don't sell or share your data with third parties, other than Google itself as the sign-in provider.
Where your data is stored
All game data is stored on our own server, not a third-party cloud analytics platform. Authentication is handled by Google's sign-in service, which has its own privacy policy governing that part of the process.
Data deletion
You can request deletion of your account and all associated scores at any time by contacting us (see the Contact page). We'll remove your data from our database.
Children's privacy
Kollatz is not directed at children under 13, and we don't knowingly collect personal information from children under that age.
Changes to this policy
If this policy changes, the update date at the top of this page will change accordingly. Continued use of Kollatz after a change means you accept the revised policy.
Contact
Questions about this policy or your data — see the Contact page.