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Find answers to common questions below, or reach out directly — we're happy to help.

Frequently Asked Questions

How do I export a PDF?

After generating your puzzles, tap the Share icon in the top-right corner of the puzzle book screen. Select "Export PDF" to generate a print-ready PDF. You can then save it to Files, print it directly, or share it via any app on your device.

Can I use the puzzles commercially?

Exported puzzles are for personal, non-commercial use only. This means you can print and enjoy them yourself, but you may not sell puzzle books made with the app or include them in paid products. See our Terms of Use for full details.

How do I restore my purchase?

If you previously purchased a feature and need to restore it — for example after reinstalling the app or switching devices — go to Settings within the app and tap "Restore Purchases". Make sure you are signed in with the same Apple ID used for the original purchase.

Does the app work offline?

Yes. All puzzle generation happens entirely on your device. You do not need an internet connection to create, solve, or export puzzles.

What grid sizes are available?

The app supports three grid formats: 4×4 (great for beginners and children), 4×6 (a compact but satisfying challenge), and the classic 9×9 grid. Each size is available across all difficulty levels.

Is my data private?

The app is designed not to collect information that directly identifies you, such as your name or email address. It may collect limited usage analytics to help improve the product. See our Privacy Policy for the full details.

Still need help?

Send us an email and we'll get back to you as soon as possible.

sudoku@twinkle.hk