Terms of Service

Last updated: March 2026

1. Agreement to Terms

By downloading, installing, or using SleepLedger ("the App"), you agree to be bound by these Terms of Service. If you do not agree to these terms, do not use the App.

2. Service Description

SleepLedger is an iOS application that reads sleep analysis, heart rate, and heart rate variability data from Apple Health to calculate sleep debt and generate personalized recovery plans with bedtime recommendations. The App also provides trend charts, widgets, and Siri Shortcuts integration.

3. In-App Purchases

SleepLedger offers optional Premium upgrades through the Apple App Store:

  • Monthly subscription
  • Annual subscription
  • Lifetime one-time purchase

Subscriptions automatically renew unless cancelled at least 24 hours before the end of the current period. Purchases are non-refundable except as required by applicable law. To request a refund, visit reportaproblem.apple.com.

4. User Conduct

You agree not to:

  • Reverse engineer, decompile, or disassemble the App
  • Modify, adapt, or create derivative works from the App
  • Use the App for any unlawful purpose
  • Attempt to circumvent any security features
  • Redistribute or sublicense the App

5. Intellectual Property

All content, features, and functionality of the App are owned by tknzk and are protected by international copyright, trademark, and other intellectual property laws. You are granted a limited, non-exclusive, non-transferable license to use the App for personal, non-commercial purposes.

6. Health Data Disclaimer

The App accesses health data from Apple Health with your permission. SleepLedger is not a medical device and is not intended to diagnose, treat, cure, or prevent any disease or health condition. The accuracy of sleep data depends on the recording device and source application. Always consult a healthcare professional for medical advice.

7. Disclaimer of Warranties

The App is provided "as is" and "as available" without warranties of any kind, either express or implied, including but not limited to implied warranties of merchantability, fitness for a particular purpose, and non-infringement.

8. Limitation of Liability

In no event shall tknzk be liable for any indirect, incidental, special, consequential, or punitive damages, including without limitation, loss of data, loss of profits, or other intangible losses, resulting from your use of or inability to use the App.

9. Modifications to the App

We reserve the right to modify, suspend, or discontinue the App at any time without notice. We shall not be liable to you or any third party for any modification, suspension, or discontinuation of the App.

10. Changes to Terms

We may update these Terms of Service from time to time. Changes will be reflected on this page with an updated date. Continued use of the App after changes constitutes acceptance of the revised terms.

11. Termination

We may terminate or suspend your access to the App at any time, without prior notice, for conduct that we believe violates these Terms or is harmful to other users or us. You may terminate your use of the App at any time by uninstalling it.

12. Governing Law

These Terms shall be governed by and construed in accordance with the laws of Japan, without regard to conflict of law principles.

13. Contact

If you have any questions about these Terms, please visit our contact page.