Terms of Service

1. The service

The App is a cage-arithmetic number logic game. It includes:

• boards from 3×3 to 7×7; digits do not repeat in any row or column, and numbers in each cage combine with the shown +, −, ×, or ÷ rule to match the target;
• puzzles bundled on the device and, if needed, generated on device, without a network download or a third-party official set;
• daily challenge, notes, undo, erase, hints, timer, error count, pause, themes, and a calculator;
• optional membership for extra hints, themes, revive, and custom error limits.

This version of the App does not contain ads. Features may change in updates; we will try to describe material changes in release notes.

The App uses Google Firebase Analytics for product analytics (such as screen views, purchase events, and share completion). Details of related data processing are set out in our Privacy Policy. Availability, terms, and privacy practices of those services are Google / Firebase’s responsibility. The App does not collect IDFA and does not request App Tracking Transparency.

2. Eligibility

You must have legal capacity to enter this agreement. If you are under 18, use the App and any paid features only with a parent or guardian’s consent and guidance. You agree to use the App lawfully and to provide accurate information if you contact us.

3. No account

The App does not offer a separate sign-up account. Progress, settings, and stats stay on the current device. Replacing, losing, or uninstalling the device/app may make local progress unrecoverable. Purchases completed through Apple can be restored with the same Apple ID via Restore Purchases.

4. Membership and in-app purchases

Paid items are billed by the Apple App Store. Prices are those shown at purchase and may vary by country or region.

• Subscriptions renew automatically unless you turn off auto-renew at least 24 hours before the end of the current period in system settings;
• After a free trial, the then-current price is charged unless you cancel before the trial ends;
• Refunds are handled by Apple. Request them through Apple Support or your purchase history; we cannot refund Apple charges directly;
• Membership benefits apply only inside this App, are non-transferable, and are described in the App and the store listing then in effect.

5. Acceptable use

You must not:

• reverse engineer, crack, modify, or interfere with the App except where the law expressly allows it;
• use the App for unlawful, infringing, or harmful activity; or
• suggest that we are sponsored by, affiliated with, or licensed by any third-party brand, event, or rights holder in a misleading way.

6. Intellectual property

The App’s software, interface, copy, icons, themes, bundled puzzle set, and on-device generation logic are owned by us or our licensors. These Terms do not transfer any intellectual property to you. We grant only a limited, revocable license to use the App for personal, non-commercial entertainment.

7. Disclaimer and limitation of liability

The App is provided “as is” for casual entertainment. To the fullest extent permitted by law, we are not liable for lost progress caused by device failure, OS updates, or user error; interruptions of third-party services (including Apple); or indirect, incidental, or consequential damages arising from use or inability to use the App. Our aggregate liability to you will not exceed the amount you actually paid us for the App in the twelve months before the claim (or zero if you paid nothing). Some jurisdictions do not allow limits on implied warranties or liability; those limits may not apply to you.

8. Changes and termination

We may update the App or these Terms. Material changes will be noted in an update, on this page, or by another reasonable method. Continued use means you accept the change. We may suspend or end the service for compliance, security, or operational reasons. You may uninstall the App at any time. Canceling and refunding an existing subscription still follows Apple’s rules.

9. Governing law

These Terms are governed by the laws of the People’s Republic of China, excluding conflict-of-law rules. The parties will first try to resolve disputes amicably. If that fails, courts with jurisdiction at our domicile will hear the dispute. Mandatory consumer-protection rules in your country of residence that cannot be waived still apply.

10. Contact