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.
Analytics
Kollatz uses Google Analytics to understand overall traffic — which pages are visited, how often, and roughly where from. This works through cookies and collects general usage data, not anything tied to your gameplay account. You can read Google's own privacy policy for details on how Analytics data is handled. Kollatz does not use this data for advertising, and does not currently show ads or share data with advertising networks.
What we don't collect
Beyond the Google Analytics traffic data described above, we don't collect location data, contacts, photos, or anything from your device beyond what's described in this policy.
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
Your gameplay data (scores, progress, account info) is stored on our own server, not a third-party cloud platform. Traffic data from Google Analytics is processed by Google, under their own terms. Authentication is handled by Google's sign-in service as well, 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.