Privacy Policy
DK Squared Studio is the trading name of David Kuchel, a sole proprietor (see the Impressum for contact details), who is the controller responsible for data processing under the GDPR ("we," "us," "our"). We make DK Sudoku (the "App"). This policy explains what data the App and this website handle, in plain language.
The short version
DK Sudoku doesn't have accounts, doesn't use analytics or advertising, and doesn't send your puzzle data anywhere. Everything about how you play — your progress, statistics, and settings — stays on your device. The only outside parties involved at all are Apple/Google (to process your purchase and, if you choose to use it, Game Center/Play Games Services), and neither of those receives any of your actual gameplay data from us.
Data stored on your device
The App stores the following locally, in its own private storage area:
- Your saved puzzle-in-progress, notes/pencil marks, and settings
- Your play history and statistics (times, scores, streaks, mistake counts)
- Your Daily Challenge progress
- Whether you've unlocked the full app via in-app purchase
None of this is transmitted to us or to any third party. We have no server, and we cannot see any of it. If you uninstall the App or clear its storage, this data is gone.
Purchases
DK Sudoku is unlocked with an in-app purchase (a one-time purchase or a subscription, your choice). That purchase is handled entirely by Apple (App Store) or Google (Play Store) — we never see your payment details, and we don't operate any payment infrastructure of our own. Apple's and Google's own privacy policies govern that transaction.
Game Center / Play Games Services (optional)
If you choose to sign in for Achievements and Leaderboards, the App uses Apple's Game Center (iOS) or Google Play Games Services (Android). Signing in shares your platform account identifier (and whatever alias/photo you've already set up with that account) directly between your device and Apple/Google — we don't receive, see, or store that information ourselves. Achievement unlocks and leaderboard scores you earn are sent to Apple/Google to display within their Game Center/Play Games systems. This is entirely optional — the App works fully without signing in, just without shared leaderboards or achievement syncing across devices.
Apple's and Google's own privacy policies apply to their handling of this data:
What we don't do
- We don't use analytics, crash reporting, or advertising SDKs.
- We don't collect your name, email, location, contacts, photos, or any device identifiers.
- We don't track you across apps or websites.
- We don't sell or share your data, because we don't collect any to begin with.
This website
This website is a static site. It has no forms, accounts, cookies, or analytics, and it loads no third-party scripts, fonts, or trackers — its typefaces are served from the site itself.
The site is hosted by Cloudflare, Inc. (Cloudflare Pages). When you visit, the hosting provider processes technical data such as your IP address, browser type, and the pages requested, in server logs, in order to deliver the site and protect it from abuse. This is our legitimate interest under Art. 6(1)(f) GDPR. We do not receive or evaluate this data ourselves beyond what the provider makes available.
If you email us, we use your email address and message only to reply to you.
Notifications
If you turn on the optional daily reminder, it's scheduled entirely on your device using your operating system's local notification system. No data about this leaves your device.
Children's privacy
DK Sudoku doesn't knowingly collect personal information from anyone, of any age, because it doesn't collect personal information at all.
Your rights
Because we don't operate any servers or hold any personal data about you, there is generally nothing for us to access, correct, or delete on your behalf — the data described above already lives entirely on your own device, under your own control. For purchase records or Game Center/Play Games account data, please contact Apple or Google directly using the links above. If you're in the EU/EEA, you also have the right to lodge a complaint with your local data protection authority.
Changes to this policy
If this policy changes — for example, if a future version of the App adds an account system or cloud sync — we'll update this document and the "Last updated" date above, and any new data collection will be described here before it's turned on.
Contact us
Questions about this policy or the App's data practices? Email us at info@dk-squared-studio.com.