Privacy Policy

Last updated: 1 October 2026

sudoku42 stores an anonymous account ID and the game data needed to run the app: game IDs, moves, notes, puzzle difficulty, and timelines. This lets you play, sync, and view your games. This data is stored with Google Firebase.

If you join a multiplayer game, the app can send notifications about activity in that game using Firebase Cloud Messaging.

The app uses Google AdMob to show banner and rewarded ads. Google may collect information about your device and ad interactions to show and measure ads. You can read more in the Google Privacy Policy and Google’s AdMob information for app users.

iOS waitlist

If you join the iOS waitlist, we store your email address, signup time, consent version, campaign source, and a coarse device category (such as iPhone, iPad, Android, or desktop) with Google Firebase to measure interest and email you about the iOS launch. We do not use the list for a newsletter or sell it. Signing up does not reserve a release date or guarantee a launch. Email addresses are not verified at signup.

Shared links include a campaign tag; they do not include your email address or a personal ID. To leave the list or request deletion, email manuel@sudoku42.com. We delete the waitlist after the launch notification, or if the launch is cancelled.

Contact

For questions or privacy requests, email manuel@sudoku42.com.