Terms of Service

Effective March 2023 · Last updated September 23, 2026

These Terms of Service ("Terms") are a contract between you and TeraThreshold LLC ("TeraThreshold", "we", "us") governing your use of the TeraThreshold iOS application (the "App"), the website at terathreshold.com (the "Site") and related services (together, the "Service"). By creating an account or using the Service you agree to these Terms and to our Privacy Policy. If you do not agree, do not use the Service.

1. Who can use the Service

The Service is offered in the United States. You must be at least 16 years old, located in the United States, and able to form a binding contract. If you use the Service on behalf of a team or organization, you confirm that you are authorized to accept these Terms for it.

2. Your account and connected services

You sign in with your Garmin account (or with Apple where offered). You are responsible for keeping those credentials secure and for all activity under your account. Connecting Garmin, Withings or any other service is subject to that provider's own terms, and you authorize us to access the data described in the Privacy Policy on your behalf. You may disconnect a service at any time from the App or from the provider's settings; some features will stop working without it.

3. Not medical advice

TeraThreshold produces scores, estimates and suggestions such as form scores, injury-risk scores, training-load metrics, race predictions, training paces, heart-rate zones, drills and recovery protocols. These are computed from your training data using statistical models and are provided for informational and educational purposes only. They are not medical advice, diagnosis or treatment, and they are not a substitute for the judgment of a physician, physiotherapist or qualified coach.

An injury-risk score is an estimate, not a prediction that you will or will not get injured. Always consult a qualified professional before changing your training in response to pain, illness or injury, and stop exercising and seek medical help if you experience symptoms such as chest pain, dizziness or severe pain. You are solely responsible for your training decisions and for any consequences of them.

4. Subscriptions, trials and payment

• Parts of the Service are free. Additional features ("Pro") require a paid subscription purchased through Apple's App Store as an auto-renewing subscription.
• New accounts receive a trial period of Pro as described in the App. When the trial ends, Pro features lock unless you subscribe.
• Prices are shown in the App at the time of purchase. Subscriptions renew automatically at the same price and term unless you cancel at least 24 hours before the end of the current period. Manage or cancel subscriptions in your Apple ID settings; deleting the App does not cancel a subscription.
• Payments, refunds and billing disputes are handled by Apple under Apple's terms. We cannot issue refunds for purchases made through the App Store.
• We may change prices or the features included in Free and Pro. Price changes take effect at the next renewal after notice to you as required by Apple.

5. Beta and TestFlight

While the App is distributed through Apple's TestFlight program it is pre-release software. It may contain errors, change without notice, lose data or stop working, and features available during the beta may not be available afterward. Your use of TestFlight builds is also subject to Apple's TestFlight terms.

6. Your content and data

You own the data you provide and the data we retrieve from your connected services on your behalf. You grant TeraThreshold a limited, worldwide, non-exclusive license to store, process, analyze and display that data solely to provide, secure and improve the Service. We may use data that has been aggregated or de-identified so that it no longer identifies you to improve our models and the Service. You can delete your account and your data as described in the Privacy Policy.

7. Acceptable use

You agree not to:

• use the Service for any unlawful purpose or in violation of a connected provider's terms;
• access or attempt to access another user's account or data;
• reverse engineer, decompile, scrape, or copy the Service or its models, except where the law allows despite this restriction;
• interfere with the operation or security of the Service, including by probing, overloading or circumventing access controls;
• resell, sublicense or provide the Service to third parties, or use it to build a competing product;
• upload malicious code or falsified data intended to disrupt the Service.

8. Intellectual property

The Service, including its software, models, scoring methods, design, text and graphics, is owned by TeraThreshold or its licensors and protected by intellectual-property laws. Subject to these Terms, we grant you a personal, non-transferable, revocable license to use the App on Apple devices you own or control for your own non-commercial training. All rights not expressly granted are reserved. Garmin is a trademark of Garmin Ltd.; Withings, Apple, App Store and TestFlight are trademarks of their respective owners. TeraThreshold is not affiliated with or endorsed by them.

9. Third-party services

The Service depends on data and services from third parties, including Garmin, Withings and Apple. We do not control them and are not responsible for their availability, accuracy or conduct. If a provider changes or withdraws access, related features may change or stop working.

10. Termination

You may stop using the Service and delete your account at any time. We may suspend or terminate your access if you breach these Terms, if required by law, or if we discontinue the Service, with notice where reasonably possible. Sections that by their nature should survive termination, including 3, 6, 8, 11, 12, 13, 14 and 16, survive.

11. Disclaimers

THE SERVICE IS PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTIES OF ANY KIND, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY AND NON-INFRINGEMENT. WE DO NOT WARRANT THAT THE SERVICE WILL BE UNINTERRUPTED, ERROR-FREE OR SECURE, THAT DATA WILL NOT BE LOST, OR THAT ANY SCORE, ESTIMATE OR SUGGESTION WILL BE ACCURATE OR SUITABLE FOR YOU. Some states do not allow the exclusion of certain warranties, so some of these exclusions may not apply to you.

12. Limitation of liability

TO THE FULLEST EXTENT PERMITTED BY LAW, TERATHRESHOLD AND ITS MEMBERS, MANAGERS, EMPLOYEES AND SUPPLIERS WILL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL OR PUNITIVE DAMAGES, OR FOR ANY LOSS OF DATA, PROFITS OR GOODWILL, OR FOR ANY PERSONAL INJURY ARISING FROM YOUR TRAINING DECISIONS, ARISING OUT OF OR RELATING TO THE SERVICE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. OUR TOTAL LIABILITY FOR ALL CLAIMS RELATING TO THE SERVICE WILL NOT EXCEED THE GREATER OF THE AMOUNT YOU PAID US IN THE TWELVE MONTHS BEFORE THE CLAIM OR FIFTY US DOLLARS. Some states do not allow these limitations, so they may not apply to you in full.

13. Indemnity

You agree to indemnify and hold TeraThreshold and its members, managers and employees harmless from claims, damages and expenses, including reasonable legal fees, arising from your breach of these Terms or your misuse of the Service.

14. Governing law and disputes

These Terms are governed by the laws of the State of California, United States, without regard to conflict-of-law rules. Any dispute that cannot be resolved informally will be brought in the state or federal courts located in California, and you consent to their jurisdiction, except that either party may seek injunctive relief in any court of competent jurisdiction, and either party may bring an eligible claim in small-claims court. Nothing in this section limits any rights you have under the consumer-protection laws of the state where you live.

15. Changes to these Terms

We may update these Terms. We will post the new version at terathreshold.com/terms with a new effective date and, for material changes, notify you in the App or by email before they take effect. Continued use after the effective date means you accept the updated Terms.

16. General

These Terms and the Privacy Policy are the entire agreement between you and TeraThreshold about the Service. If any provision is found unenforceable, the rest remains in effect. Our failure to enforce a provision is not a waiver. You may not assign these Terms; we may assign them in connection with a merger, acquisition or sale of assets. Apple is not a party to these Terms and has no obligation to provide support or maintenance for the App, but Apple and its subsidiaries are third-party beneficiaries of these Terms and may enforce them against you.

17. Contact

Questions about these Terms: [email protected].