Last updated: 14 September 2026

The short version

The game works entirely on your device. There are no accounts, no logins, no ads, and no advertising identifiers. From version 1.2 the app sends anonymous usage statistics so I can see which parts of the game people actually use. You can turn that off in Settings → Privacy, and the game works identically either way.

What is collected

When Share anonymous usage data is on, the app sends a small, fixed set of events:

• Tutorial: that the tutorial was started, completed, skipped, or abandoned — and at which of its three steps.
• Games: that a game was started, finished, abandoned, or resumed, with the mode (solo or pass-and-play), the difficulty, who moved first, the outcome (win, loss, or draw), the number of moves, how many hints and undos were used, and how long the game lasted.

That list is the complete set. It is a closed list in the source code, not a general-purpose logger.

Alongside each event, the analytics provider attaches standard technical information: app version and build, operating system and version, device model, platform, language, time zone, and whether the build is a simulator, debug, or TestFlight build.

What is never collected

• Your name, email address, phone number, or any contact information.
• Your location.
• Your advertising identifier (IDFA). The app does not use one, does not show ads, and never presents an App Tracking Transparency prompt.
• The contents of your games as stored on your device — your saved game, your statistics, and your settings stay on your device and are never uploaded.

The anonymous device identifier

Each event carries an anonymous identifier so repeat sessions can be counted as one returning player rather than many new ones.

That identifier is a salted SHA-256 hash of Apple's identifierForVendor, computed on your device before anything is sent. The hash cannot be reversed into the original identifier. The salt is unique to this app, which means the same device produces a different value in this app than in any other app I publish — your usage here cannot be correlated with any other app.

It is not linked to your identity, because there is no identity to link it to: the app has no accounts.

Who processes the data

Anonymous usage data is processed by TelemetryDeck, a privacy-focused analytics provider based in Germany. It is the only third-party service the app contacts, and the only third-party SDK in the app. No data is sold, shared with advertisers, or used to build a profile of you.