SOLID SUDOKU

Privacy Policy

Solid Sudoku

Last updated: July 21, 2026

Introduction

Solid Sudoku is made by DoorGames, LLC. We built it to be a calm, private place to play Sudoku — no account, no ads, no tracking. This policy explains exactly what the app does and doesn't collect, and who processes it on our behalf. It applies to the iOS and Android versions of Solid Sudoku.

What we don't collect

We do not collect, and never ask for:

• Your name, email address, phone number, or any account — Solid Sudoku has no sign-in.
• Your precise or coarse location.
• Your photos, contacts, calendar, or files.
• Advertising identifiers (Apple's IDFA or Google's Advertising ID).
• Your browsing or search history.
• Any payment or card details — if you subscribe, those stay with Apple or Google.

What we do collect (and why)

Your personal game statistics stay on your device. Games played, win rate, streaks, and best and average solve times are stored locally on your phone and are never transmitted to us.

Anonymous completion statistics. When you finish a puzzle, the app submits a small, anonymous record so we can show the anonymous "how you compare" percentile screen. The record contains exactly: the puzzle id (which identifies the puzzle, not you — for a daily challenge it embeds that puzzle's calendar date), the difficulty, your solve time both as played and with the hint penalty added, the number of hints you used, and the number of mistakes you made. It carries no identifier of any kind: no name, no account, no device ID, no IP-based ID. It cannot be tied back to you or your device. This data is handled by Cloudflare, which hosts our statistics service.

Crash and performance diagnostics. To keep the app stable and fast, we use Sentry to capture crash reports and basic performance data. A report includes the app version, operating-system version, device model, and a stack trace when something goes wrong. It is configured to be identifier-free: we disable personal data, store no IP address, and attach no user, device, or session identifier. Diagnostic data is retained for about 90 days for troubleshooting.

Subscriptions and purchases. Solid Sudoku is free to download with a 7-day trial; after that, an optional annual subscription or one-time lifetime unlock removes the trial limit. If you purchase, we use RevenueCat to manage your entitlement. RevenueCat receives the transaction data that Apple or Google shares about the purchase, associated with an anonymous app-user identifier that RevenueCat generates — it is not linked to your identity, and we never receive your name or payment details. Apple and Google process the payment itself under their own privacy policies.

Anonymous usage analytics. To understand how the app is used in aggregate — for example how often games are started and completed, or which features are used — we use TelemetryDeck. TelemetryDeck identifies a device only by a salted, double-hashed value rather than a user or advertising identifier; it is not linked to you and is not used to track you across other apps or websites. All values are recorded in coarse buckets, never as free text.

What we don't do

• No ads, and no ad networks in the app.
• No tracking of you across other apps or websites, and no cross-app advertising measurement.
• We never sell your personal information.
• We do not build advertising or behavioral profiles about you.

Children's privacy

Solid Sudoku is not directed to children under 13, and we do not knowingly collect any information from children under 13 (or the equivalent minimum age in your region under COPPA and GDPR-K). If you believe a child has provided information to us, contact us and we will address it.

Your rights

Depending on where you live, you may have rights to access, correct, or delete personal data we hold about you. Because Solid Sudoku is designed to be anonymous — the gameplay and diagnostic data described above carry no identifier — we generally cannot connect that data to you, so there is no personal record for us to look up, export, or delete. If you have a question about your data, contact us and we will help.

Changes to this policy

We may update this policy as the app changes. When we do, we will revise the "Last updated" date above, and material changes will be reflected here before they take effect.

Contact

Questions about this policy or your privacy? Email us at hello@doorgames.io.