Sudoku · Terms of Service

1. Acceptance and Changes

1.1 By downloading, installing, opening, or otherwise using the Sudoku app, you accept these Terms and the Privacy Policy.

1.2 We may revise these Terms due to business changes, legal requirements, or product updates. Updated Terms will be published in the App and take effect upon publication. If you do not agree, please stop using the App; continued use constitutes acceptance.

2. Description of Services

2.1 Sudoku is a puzzle game developed and operated by us. Main features include:

• Playing sudoku puzzles by difficulty;
• Assistive tools such as pencil notes and error feedback;
• Saving and displaying completion records and weekly best times;
• Unlocking higher difficulties based on completion progress.

2.2 Features may change over time. We will notify you of material changes in the App where appropriate.

2.3 The App is intended for personal, non-commercial entertainment, unless otherwise required by law.

3. Eligibility

3.1 You represent that you have the legal capacity to use the App. If you are a minor, you should use the App only with a guardian’s consent and guidance.

3.2 You must use a legitimate client and obtain puzzles / submit records only through our designated backend services.

4. Device Identifier and Game Records

4.1 The App does not provide account registration or login. After installation, it generates an anonymous device identifier (deviceNo) locally to associate completion records, unlock status, and weekly best scores.

4.2 Changing devices, clearing app data, or reinstalling may change deviceNo, and historical records may no longer be linked.

4.3 Game records are stored on our servers and associated with deviceNo. See the Privacy Policy for details.

5. Prohibited Conduct

5.1 You must not:

• Use the App for any unlawful or improper purpose;
• Use crawlers, bots, cheats, or other automated means to access or disrupt the service or falsify results;
• Reverse engineer, decompile, crack, or bypass security mechanisms of the App;
• Launch denial-of-service attacks or otherwise harm service stability;
• Access, alter, or delete data without authorization;
• Engage in any other conduct that violates law, these Terms, or App rules.

5.2 We may limit, suspend, or terminate service to violators and, where appropriate, refer matters to competent authorities.

6. Intellectual Property

6.1 The App (including software, UI, icons, text, visuals, puzzle bank, and presentation) is owned by us or our licensors. You may not copy, modify, publish, distribute, sell, or otherwise exploit it without our written permission.

6.2 Classic sudoku rules are not claimed as our exclusive rights; our puzzle data, implementation, and service systems remain protected.

6.3 If you believe content in the App infringes your rights, contact us under Section 15 with supporting materials. We will handle the request within a reasonable time.

7. Third-Party Services

7.1 The App relies on our backend for puzzle delivery and record storage. Data processing is described in the Privacy Policy.

7.2 If we later integrate third-party SDKs or sign-in, we will disclose them in the Privacy Policy and obtain consent where required.

8. Fees

8.1 Core features are currently free. We may introduce paid features later; prices and refund rules will be clearly disclosed before purchase.

9. Disclaimer

9.1 The App is provided “AS IS” and “AS AVAILABLE.” To the maximum extent permitted by law, we make no warranties that:

• the service will be uninterrupted, timely, secure, or error-free;
• puzzle uniqueness, difficulty labels, or timing statistics are absolutely accurate;
• networks or infrastructure will always be stable.

9.2 We are not liable for losses caused by force majeure, your misuse, third-party failures, or loss of record linkage after clearing data or changing devices.

10. Limitation of Liability

10.1 To the maximum extent permitted by law, we are not liable for indirect, incidental, special, punitive, or consequential damages, including lost profits, data, or goodwill.

10.2 Our aggregate liability related to the App shall not exceed the fees you paid us for the App in the preceding twelve months; if the App was free at the relevant time, our aggregate liability shall not exceed RMB 100.

10.3 These limitations do not apply where liability cannot be limited by law (for example, willful misconduct or gross negligence causing personal injury).

11. Suspension and Termination

11.1 You may stop using the App at any time, including by uninstalling it.

11.2 We may suspend or terminate service without prior notice if you violate Section 5, if required by law, or if needed to protect system security or other users.

11.3 After termination, data associated with deviceNo will be handled under the Privacy Policy retention rules.

12. Privacy

For how we collect, use, store, and protect information, see the Privacy Policy. That policy and these Terms together form the complete agreement.

13. Governing Law and Disputes

13.1 These Terms are governed by the laws of the People’s Republic of China (excluding Hong Kong, Macau, and Taiwan).

13.2 Disputes should first be resolved through friendly negotiation; failing that, either party may bring suit before a court with jurisdiction at our place of operation.

13.3 If you use the App outside mainland China, you still agree to these Terms, subject to any mandatory consumer-protection rules that apply in your jurisdiction.

14. Miscellaneous

14.1 Severability. If any provision is invalid, the remaining provisions remain in effect.

14.2 No waiver. Failure to enforce a right is not a waiver of that right.

14.3 Assignment. You may not assign these Terms without our written consent; we may assign them to an affiliate or successor upon reasonable notice.

14.4 Entire agreement. These Terms and the Privacy Policy constitute the entire agreement regarding the App.

15. Contact Us

If you have questions about these Terms, contact us at:

• Operator: Hope Tech
• Email: hope.tec.xyz@gmail.com

We will respond within 15 business days.