Terms of Service

Last updated: May 2026

1. Agreement to Terms

By downloading, installing, or using Sextant Vitality ("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

Sextant Vitality is an iOS application that combines HealthKit data (VO₂max, HRV, resting heart rate, sleep, walking speed, workouts) with manually entered blood lab results and intervention logs to compute a 0–100 Vitality Score and supporting trends. It is positioned as a self-understanding tool for midlife men, not a medical device.

3. In-App Purchases

Sextant Vitality offers optional upgrades through the Apple App Store:

Subscriptions automatically renew unless cancelled at least 24 hours before the end of the current period. You can manage or cancel subscriptions at any time via your App Store account settings. Purchases are non-refundable except as required by applicable law. To request a refund, visit reportaproblem.apple.com.

4. Free Trial

The yearly Premium plan includes a 7-day free trial for new subscribers. The monthly Premium plan does not include a free trial. Eligibility for the yearly trial is determined by Apple based on your prior subscription history. The trial converts to a paid subscription unless cancelled at least 24 hours before it ends.

5. User Conduct

You agree not to:

6. Intellectual Property

All content, features, and functionality of the App — including the Meridian logo, the Vitality Score formula, brand assets, and the lab panel catalog — 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.

7. Health Data Disclaimer

Sextant Vitality is not a medical device and is not intended to diagnose, treat, cure, or prevent any disease or health condition. The Vitality Score is a wellness indicator based on statistical patterns, age-banded reference values, and personal baselines — it does not constitute medical advice. Always consult a qualified healthcare professional for medical guidance, particularly before changing medications, supplements, exercise regimens, or considering testosterone replacement therapy (TRT) or other hormonal interventions.

8. Lab Result Reference Ranges

Reference ranges shown for lab panels (Total T, ApoB, hs-CRP, etc.) are conservative consensus values from public guidelines and are for orientation only. Your actual reference range depends on the laboratory that performed the test, the assay method, and your individual circumstances. Always defer to your physician's interpretation of your own results.

9. 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.

10. 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.

11. 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. Lifetime purchasers retain access to features available at the time of purchase to the extent technically feasible.

12. Changes to Terms

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

13. Termination

We may terminate or suspend your access to the App 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.

14. Governing Law

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

15. Contact

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