Sudoku Coach Privacy Policy
Your puzzles and learning progress stay on your devices and, if you keep iCloud Sync on, in your own iCloud account. There is no Sudoku Coach account. Only if you allow it, we receive anonymous usage statistics and crash reports through Google Firebase. The free version shows ads from Google AdMob; Premium removes them. We never sell personal data.
Data stored on your device
Your settings, your learning progress (current level, skill rating, lessons completed, technique mastery and review schedule, practice days, and certificates), puzzles in progress, and the history of puzzles you solved (time, hints used, and mistakes) are stored on your iPhone or iPad.
If you share a puzzle, the display name you type is stored with it on your device. Home Screen widgets and the Apple Watch app show a short summary (practice days and recent results) that stays on your devices.
None of this is sent to us or to any server we operate.
iCloud Sync
With iCloud Sync on (the default), your settings, learning progress, and shared puzzles are also saved in your iCloud account using Apple's iCloud key-value storage, so your other devices stay in step. Apple stores and protects this data under Apple's privacy policy; we cannot access it.
You can turn iCloud Sync off at any time in the app's Settings. From then on nothing new is saved to iCloud.
Camera and photos (puzzle scanner)
If you scan a puzzle from paper or a screenshot, the app asks for access to your camera or photos. The image is read on your device with Apple's Vision framework to recognise the digits. The image is not saved by the app and is never uploaded.
Coaching tips with Apple Intelligence
On devices that support Apple Intelligence, some coaching tips are written by Apple's on-device language model. The prompt contains only puzzle context, such as the difficulty or the technique you just used. It is processed entirely on your device and never sent to us.
Advertising (free version)
The free version shows ads from Google AdMob: a full-screen ad occasionally between puzzles, an ad card on a few screens such as Home and the puzzle review, and optional videos you can choose to watch to open an advanced lesson for 24 hours. Ads are never shown while you are solving a puzzle.
To show and measure ads, Google's Mobile Ads SDK collects device and app information, your IP address and approximate location derived from it, ad interactions, and diagnostic data. It uses Apple's advertising identifier (IDFA) only if you allow tracking when iOS asks; otherwise ads are shown without it.
In the European Economic Area, the United Kingdom, Switzerland, and US states with privacy laws, Google's consent message lets you choose how your data is used for ads. You can change those choices at any time in Settings > Ad privacy choices. Google's use of data is described at https://policies.google.com/technologies/partner-sites.
With Premium, no ads are shown and the ads SDK is not started.
Usage statistics and crash reports (only if you allow)
After setup, the app asks once whether to share usage statistics and crash reports. Nothing is collected until you tap Allow, and Don't allow is just as easy to tap. This applies to everyone, in every region.
If you allow it, we receive through Google Firebase (Analytics and Crashlytics): which features you use, for example "lesson completed" with the technique and score, "puzzle completed" with the difficulty, time, hints, and mistakes, placement and exam results, and settings changes; your Premium status and display settings; whether a purchase you started completed; ad events, including the estimated value of an ad; crash and error reports; device and app information such as model, iOS version, language, and app version; random app identifiers (a Firebase app-instance ID and a Crashlytics installation ID); and an approximate region that Google derives from your IP address.
We never include text you type, such as your display name. These statistics are not linked to your identity and are not used by us for advertising.
You can change your mind any time in Settings > Share usage and crash data. Turning it off stops collection, resets the analytics identifier on your device, and deletes crash reports that have not been sent yet. To delete data already sent, email us.
Usage statistics are kept for 2 months and crash reports for 90 days. Google processes this data for us under Google's data processing terms, and it may be processed outside your country.
Purchases
Sudoku Coach Premium is a one-time purchase through Apple's App Store. Apple processes the payment; we never see your name, Apple ID, or payment details. The app checks on your device whether Premium is active using Apple's StoreKit, and Family Sharing is supported.
Notifications
The daily practice reminder and the weekly learning summary are scheduled locally on your device. They are optional and can be turned off in the app or in iOS Settings. No push notification service is used.
Sharing puzzles and certificates
When you share a puzzle, the link contains the puzzle (a number that recreates it), its difficulty, the date, and the display name you chose. When you share a certificate, the image is created on your device. Both go only where you send them in the iOS share sheet.
Backups
If you use iCloud Backup or a computer backup, iOS may include Sudoku Coach data in that backup. Those backups are controlled by Apple and by you, not by us.
Deleting your data
Open Settings in the app and tap Delete all data. This removes your progress, puzzles, and settings from the device and from iCloud Sync. Deleting the app also removes the data stored on that device. A Premium purchase belongs to your Apple ID and can be restored at any time.
Your rights
Depending on where you live, laws such as the GDPR (EU/UK) and CCPA (California) give you rights to access, correct, export, or delete your personal data, and to object to its processing.
Your learning data stays on your devices and in your iCloud account, so you can delete it directly in the app. For usage statistics and crash reports you allowed, turn sharing off in Settings or email us to delete what was sent; for ads, use Settings > Ad privacy choices. We do not sell personal data. If you have a question or complaint, email us; you may also contact your local data protection authority.
Children
Sudoku Coach is designed for adults and is not directed to children under 13. We do not knowingly collect personal data from children.
Changes to this policy
If we change what the app collects, we will update this page and the App Store privacy label before that version is released.
Contact
Sudoku Coach is published by ADEPT LABS TECHNOLOGY COMPANY LIMITED, Vietnam. Questions about this policy or your data: admin@adept-labs.com.