DK Sudoku Privacy Policy

English · Deutsch

1. Who we are

This privacy policy applies to the DK Sudoku mobile app for Android and iOS (the "App"). The App is developed and published by David Kuchel, trading as DK Squared Studio, a sole proprietor based in Germany ("we", "us", "our"). For the processing we carry out ourselves, we are the controller within the meaning of the EU General Data Protection Regulation (GDPR).

Contact: support@dk-squared-studio.com. Our postal address is in the Impressum.

This policy covers the App only. Our website has its own privacy policy.

2. The short version

• The App has no accounts, no ads, no analytics and no crash-reporting tools, and we run no servers of our own.
• Your games, statistics and settings are stored on your device. We never receive them.
• Purchases go through Google Play (or the Apple App Store). We never see your payment details.
• Achievements and leaderboards use Google Play Games Services (or Apple Game Center). If you use Play Games, Google processes your Play Games profile and the scores and achievements you earn.
• If you email us, we use your message only to answer it.

3. Data stored only on your device

The App keeps the following in its own private storage on your device:

• the puzzle in progress, notes and pencil marks
• your play history and statistics (times, scores, streaks, mistakes, hints used)
• your Daily Challenge progress
• your settings, including language and reminder time
• how many free puzzles you have played, and whether the App is unlocked

The App never sends this data to us or to anyone else. Deleting the App, or clearing its storage in your device settings, deletes it permanently.

If you have turned on device backup, Android or iOS may include the App's data in your own backup, which Google or Apple stores in your account. That backup is under your control and governed by their terms. We cannot access it.

4. Purchases and subscriptions

You can play 20 puzzles for free. After that, you can unlock the full App with either a one-time purchase or an auto-renewing subscription billed every three months. Both unlock exactly the same content.

Purchases are processed entirely by Google Play on Android and by the Apple App Store on iOS. They collect your payment details and account information under their own privacy policies. We never receive your card or bank details, your name or your email address.

To unlock the App, and to notice when a subscription ends or a purchase is refunded, the App asks the store on your device which DK Sudoku purchases your store account owns. It does this when it starts and whenever you return to it. The answer is stored on your device only.

For our accounting and tax obligations, Google and Apple give us transaction records such as an order number, the product, the price, the date and the country or region of purchase. We use these only for accounting and tax purposes and to handle support requests, never to identify you or build a profile. Legal basis: Art. 6(1)(b) GDPR (performance of the contract) and Art. 6(1)(c) GDPR (statutory retention duties). We keep them for the retention periods required by German commercial and tax law.

5. Google Play Games Services (Android)

The App uses Google Play Games Services, provided by Google, for achievements and leaderboards. When the App starts, it tries to connect to Play Games. If you have a Play Games profile and automatic sign-in is enabled, Google signs you in and briefly shows a "Signed in as…" banner. If you don't have a profile, or you have turned automatic sign-in off, the App doesn't connect and works fully without Play Games.

While you are connected, the following data is processed by Google:

• Your Play Games identity: your player ID, gamer name (gamertag) and avatar. Google shares these with the App so it can show your profile.
• Game progress: the achievements you unlock and the winning scores you post to the six difficulty leaderboards. When you connect, the App also sends scores and achievements from your on-device history, so that wins played offline or before you connected are not lost.
• Google also collects usage and diagnostic data about the Play Games service itself, under its own privacy policy.

Other players may see your gamer name, avatar, scores and achievements, depending on the visibility you have chosen in your Play Games profile. We can see leaderboards in the same way, and Google gives us aggregated statistics in the Play Console. We do not copy or store your Play Games identity on any system of our own.

Legal basis: Art. 6(1)(b) GDPR, to provide the achievements and leaderboards you use, and Art. 6(1)(f) GDPR, our legitimate interest in offering these platform features to players who have set up Play Games.

Your choices: you can turn off automatic sign-in for games in your Play Games settings, or sign out there. You can delete your Play Games data for DK Sudoku, or your entire Play Games account, from your Play Games profile or your Google Account.

Google may process this data outside the EU, including in the USA. Google LLC is certified under the EU–US Data Privacy Framework. See Google's Privacy Policy.

6. Apple Game Center (iOS)

On iOS, the App uses Apple's Game Center for the same achievements and leaderboards, in the same way as described in section 5. Apple processes your Game Center identity, scores and achievements under Apple's Privacy Policy. You can sign out of Game Center in your device's settings.

7. Contacting us and "Suggest an improvement"

"Suggest an improvement" in the App's settings opens your own email app with a new message to support@dk-squared-studio.com. The App fills in the App version and the platform (Android or iOS) so we can reproduce problems. Nothing is sent unless you send the email yourself.

When you email us, we process your email address, your message and anything you choose to include, only to answer you. Legal basis: Art. 6(1)(b) GDPR where your message concerns a purchase or the App's use, and Art. 6(1)(f) GDPR otherwise. We delete the correspondence once your request is resolved, unless we are required to keep it by law.

8. Ratings and reviews

The App may occasionally offer the store's own rating dialog. Google or Apple handles this entirely. If you post a review, it is published under your store profile name and visible to us and the public, under the store's terms.

9. Crash and performance information

The App contains no crash-reporting or analytics tools. If you have allowed your device to share usage and diagnostic data with Google or Apple, they may give us crash reports and performance statistics, such as Android vitals in the Play Console. These reports contain technical information like the device model, OS version and the App's state when it crashed. They do not identify you to us.

10. Notifications and permissions

The optional daily reminder is scheduled on your device by its operating system. No data about it leaves your device. On Android, the App requests:

• Notifications, only when you turn the reminder on
• Run at startup, so a scheduled reminder survives a device restart
• Google Play billing and network access, used by Google Play Billing and Play Games Services

11. What we don't do

• We don't show ads or use your device's advertising ID.
• We don't use analytics, tracking or profiling, within the App or across apps and websites.
• We don't access your location, contacts, photos, microphone or camera.
• We don't sell or rent personal data to anyone.

12. Children

DK Sudoku is suitable for all ages but is not designed specifically for children. We don't knowingly collect personal data from children. Purchases and Play Games use by minors are subject to Google's and Apple's account rules, including parental controls such as Google Family Link.

13. Your rights

Under the GDPR you have the right to access your personal data (Art. 15), to have it corrected (Art. 16) or erased (Art. 17), to restrict its processing (Art. 18), to data portability (Art. 20) and to object to processing based on our legitimate interests (Art. 21). To exercise these rights for data we hold, such as your emails or transaction records, contact us at the address above.

We hold almost no personal data about you: your game data stays on your device, and Google or Apple hold your purchase and Play Games or Game Center records. For those, use the tools and contacts they provide.

You also have the right to lodge a complaint with a data protection supervisory authority, in particular in the EU member state where you live or work.

14. Deleting your data

The App has no account to delete. To delete your data:

• On your device: clear the App's storage in your device settings, or uninstall the App.
• Play Games: delete your DK Sudoku data or your Play Games account from your Play Games profile.
• Emails to us: ask us at support@dk-squared-studio.com. Transaction records we are legally required to keep are deleted when the retention period ends.

15. Changes to this policy

If the App's handling of data changes, for example if a future version adds accounts or cloud sync, we will update this policy and its date before the change takes effect, and describe any new processing here first.

16. Contact

Questions about privacy in DK Sudoku: support@dk-squared-studio.com
David Kuchel, DK Squared Studio — full contact details in the Impressum.