Privacy Policy

Last updated: 3 August 2026

This policy covers the Sudoku mobile app for Android and iOS, and this website. The short version: the app has no accounts and needs no network to work, so there is no profile of you for us to keep.

1. What the app stores

The Sudoku app keeps the following on your device only, using the standard app storage your operating system provides:

• The puzzle you are in the middle of, saved after every move so Continue works.
• Your best time for each difficulty, and your Daily Challenge history and streak.
• Your settings: language, colour theme, sound and haptics, and whether you have seen the how-to-play screen.
• If you choose a photo as the board background, a copy of that image inside the app's own private folder.

None of this is transmitted to us or to anyone else. It is not backed up to an account, because there is no account. Removing the app removes all of it.

2. Puzzles are generated on your phone

Every grid — Classic and Daily Challenge alike — is generated by the app itself. Nothing is downloaded, so nothing about which puzzle you played, how long you took, or how many mistakes you made ever leaves the device. The Daily Challenge is identical for everyone on a given date because it is seeded from the date, not because a server handed it out.

3. Photos

Setting your own background asks the system photo picker for one image. The app copies that single image into its private storage so it survives the picker's temporary permission, and does nothing else with it. It is never uploaded, and the app does not read your photo library beyond the image you pick.

4. Advertising

The app displays banner ads through Google AdMob. To serve and measure those ads, Google may collect information such as your device's advertising identifier, IP address, device type and general location. This happens inside Google's SDK; we do not receive that data and cannot see who you are from it.

Google's handling of that data is described in Google's advertising policy and Google's privacy policy.

You have control over it at the operating-system level:

• Android: Settings → Google → Ads, where you can reset or delete your advertising ID.
• iOS: Settings → Privacy & Security → Tracking, and the permission prompt the app shows on first launch.

5. What we do not do

• No account, no email address, no sign-in with Google, Apple or anything else.
• No analytics or behavioural tracking SDK in the app.
• No selling or sharing of personal information — we hold none to sell.
• No access to contacts, microphone, camera, precise location or files, beyond the one photo you may pick yourself.

6. This website

The site is a set of static pages describing the app. Like any web server, it writes access logs — IP address, browser and operating system, timestamp, the page requested and the referring page — which are used to keep the site running and secure, not to profile visitors. We may also run server-side error monitoring that records technical details when a page fails.

The site sets no cookies at all — no advertising, no analytics, no preferences — and writes nothing to your browser's storage. There is no consent banner because there is nothing to consent to.

7. Children

The app is a Sudoku game suitable for a general audience and does not knowingly collect personal information from children. If you believe a child has provided personal information through something we operate, contact us and we will remove it.

8. Your data and your rights

Because everything the app records stays on your device, you already hold it all. To erase it, use the in-app reset or uninstall the app — see Your Data for the exact steps. There is no server-side copy for us to delete, and no export for us to send you.

9. Changes to this policy

If the app starts doing something this page does not describe, this page changes first, and the date at the top changes with it.

10. Contact

Questions about this policy: support@YOUR_DOMAIN.com.