Terms of Service

Effective date: 1 March 2026  ·  Last updated: 1 March 2026

1. Acceptance of Terms

By downloading, installing, or using the N of 1 application ("App", "Service"), you agree to be bound by these Terms of Service ("Terms"). If you do not agree to these Terms, do not use the App.

These Terms form a legally binding agreement between you and N of 1 ("we", "us", "our"). You must be at least 13 years of age (or the applicable age of digital consent in your country) to use the App.

2. Description of Service

N of 1 is an iOS application that enables users to design and track personal health experiments ("experiments") using health and fitness data read from Apple HealthKit. The App presents statistical comparisons between a baseline period and an intervention (trial) period to help you identify personal trends in your own health data.

The App is offered on a freemium basis: a free tier with core functionality, and a Premium subscription that unlocks additional features including AI-powered insights, advanced analytics, and unlimited concurrent experiments.

3. Not Medical Advice

N of 1 is not a medical device and does not provide medical advice, diagnosis, or treatment. The information, statistical outputs, charts, and AI-generated insights presented in the App are for informational and personal curiosity purposes only.

You should:

• Always consult a qualified healthcare professional before starting, stopping, or changing any supplement, medication, diet, or exercise programme
• Not rely on App outputs as a substitute for professional medical judgement
• Not use the App to self-diagnose or self-treat any medical condition

We expressly disclaim any liability arising from your reliance on App outputs for health-related decisions.

4. Apple HealthKit

N of 1 integrates with Apple HealthKit to read health and fitness data that you authorise. By granting HealthKit permissions, you acknowledge that:

• The App accesses only the HealthKit data types you explicitly permit through Apple's standard permission prompts
• The App is read-only — it never writes data to HealthKit
• You can revoke HealthKit permissions at any time in the iOS Settings app under Privacy & Security → Health → N of 1
• HealthKit data processed by the App remains on your device and is governed by our Privacy Policy

Use of HealthKit is subject to Apple's guidelines. You agree not to use N of 1 in any way that violates Apple's HealthKit developer guidelines.

5. User Accounts

N of 1 does not require you to create an account. All app data is stored locally on your device. There is no login, and we do not collect your name, email address, or other contact information in connection with your use of the App.

6. Subscriptions & Payments

6.1 Premium Subscription Plans

N of 1 Premium is available as:

• Monthly subscription — billed monthly
• Annual subscription — billed once per year (approximately 50% discount vs monthly)
• Lifetime access — a one-time purchase for permanent Premium access

Prices are displayed in the App at the time of purchase and may vary by region. All prices are in your local App Store currency and include applicable taxes where required by law.

6.2 Free Trial

Monthly and Annual subscriptions may include a free trial period (currently 7 days). You will not be charged during the free trial. If you do not cancel before the trial ends, your chosen subscription will begin and payment will be charged to your Apple ID account.

6.3 Billing & Renewal

Subscriptions automatically renew unless cancelled at least 24 hours before the end of the current billing period. Your Apple ID account will be charged for renewal within 24 hours before the end of each period. Subscription pricing may change; we will provide advance notice of any price increase.

6.4 Cancellation

You can cancel your subscription at any time through:

• App Settings — tap "Manage Subscription" to access Apple's subscription management
• iOS Settings — Settings → [Your Name] → Subscriptions → N of 1
• App Store — Your account → Subscriptions

Cancellation takes effect at the end of the current billing period. You retain Premium access until that date. We do not offer partial refunds for unused subscription time.

6.5 Refunds

All purchases are processed by Apple. Refund requests must be submitted directly to Apple at reportaproblem.apple.com. We are unable to process refunds directly.

6.6 Restore Purchases

If you reinstall the App or switch devices, tap Settings → Restore Purchases in the App to restore your subscription status. You must be signed in to the same Apple ID used to make the original purchase.

7. Acceptable Use

You agree to use N of 1 only for lawful purposes and in a manner consistent with these Terms. You must not:

• Attempt to reverse engineer, decompile, or disassemble the App
• Attempt to circumvent or disable any licensing, subscription, or feature-gating mechanism
• Use the App in any way that could damage, disable, or impair its operation
• Use the App to conduct experiments that could harm yourself or others
• Share your subscription credentials or attempt to provide Premium access to others without authorisation

8. Intellectual Property

All content, software, trademarks, logos, and other intellectual property in the App are owned by or licensed to us and are protected by applicable intellectual property laws. These Terms do not grant you any rights to use our intellectual property other than the limited licence to use the App as described herein.

We grant you a limited, non-exclusive, non-transferable, revocable licence to download and use the App on Apple devices you own or control, solely for your personal, non-commercial purposes, subject to these Terms.

9. Your Content

You retain ownership of all experiment names, notes, and other content you create within the App ("User Content"). Because all User Content is stored locally on your device, we do not access, store, or use your User Content on our servers.

When you use the Export Data feature, you choose where to send your exported data. We are not responsible for what happens to data after it leaves the App.

10. AI-Generated Insights

Premium subscribers can access AI-generated interpretations of experiment results. These insights are produced by a third-party AI model and are:

• For informational purposes only
• Not reviewed by medical professionals
• Based on anonymised statistical summaries, not your raw health data
• Potentially inaccurate, incomplete, or misleading in any given case

You agree not to rely on AI insights as medical advice. We make no representations about the accuracy or fitness for purpose of AI-generated content.

11. Disclaimer of Warranties

THE APP IS PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, AND NON-INFRINGEMENT.

We do not warrant that:

• The App will be error-free, uninterrupted, or free of bugs
• Statistical results produced by the App are accurate or appropriate for any medical purpose
• HealthKit data read by the App is accurate (accuracy of health sensor data depends on your device and usage)
• AI insights are accurate, complete, or appropriate for your specific situation

12. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, WE SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, INCLUDING BUT NOT LIMITED TO LOSS OF DATA, LOSS OF HEALTH OUTCOMES, PERSONAL INJURY, OR ANY OTHER DAMAGES ARISING FROM YOUR USE OF OR INABILITY TO USE THE APP.

OUR TOTAL LIABILITY TO YOU FOR ANY CLAIMS ARISING FROM THESE TERMS OR YOUR USE OF THE APP SHALL NOT EXCEED THE AMOUNT YOU PAID TO US IN THE TWELVE (12) MONTHS PRECEDING THE CLAIM, OR USD $10, WHICHEVER IS GREATER.

Some jurisdictions do not allow the exclusion or limitation of certain warranties or liabilities. In such jurisdictions, our liability is limited to the maximum extent permitted by law.

13. Indemnification

You agree to indemnify, defend, and hold harmless N of 1 and its officers, directors, employees, and agents from and against any claims, damages, losses, costs, and expenses (including reasonable legal fees) arising from: (a) your use of the App; (b) your breach of these Terms; or (c) your violation of any applicable law or third-party rights.

14. Third-Party Services

The App integrates with third-party services including Apple HealthKit, the Apple App Store, RevenueCat, and an AI provider for Premium insights. These services are governed by their own terms and privacy policies, which you should review independently. We are not responsible for the practices of any third-party service.

15. Termination

We reserve the right to terminate or suspend your access to the App at our sole discretion, without notice, for conduct that we believe violates these Terms or is harmful to other users, us, or third parties, or for any other reason.

You may stop using the App at any time by deleting it from your device. Sections 3, 8, 11, 12, 13, and 17 survive termination of these Terms.

16. Changes to These Terms

We may modify these Terms at any time. When we make material changes, we will update the "Last updated" date above and provide notice within the App. Your continued use of the App after the effective date of changes constitutes acceptance of the revised Terms. If you do not agree to the revised Terms, you must stop using the App.

17. Governing Law & Disputes

These Terms are governed by the laws of the jurisdiction in which we operate, without regard to conflict-of-law principles. Any dispute arising from these Terms or the App shall first be attempted to be resolved informally by contacting us at support@nof1.app. If informal resolution fails, disputes shall be submitted to binding arbitration or the courts of competent jurisdiction as required by applicable law.

Nothing in this section limits your rights under mandatory consumer protection laws applicable in your country.

18. Apple-Specific Terms

N of 1 is distributed through the Apple App Store. The following terms apply in addition to the rest of this agreement:

• These Terms are between you and us only, not Apple. Apple is not responsible for the App or its content.
• Apple has no obligation to provide any maintenance or support for the App.
• In the event of any failure of the App to conform to any applicable warranty, you may notify Apple and Apple will refund the purchase price (if any) for the App. To the maximum extent permitted by law, Apple has no other warranty obligation with respect to the App.
• Apple is not responsible for addressing any claims relating to the App, including product liability claims, consumer protection claims, or intellectual property infringement claims.
• Apple and its subsidiaries are third-party beneficiaries of these Terms and, upon your acceptance, Apple will have the right (and will be deemed to have accepted the right) to enforce these Terms against you as a third-party beneficiary.
• You represent and warrant that you are not located in a country subject to a US government embargo, and that you are not listed on any US government list of prohibited or restricted parties.

19. Entire Agreement

These Terms and our Privacy Policy constitute the entire agreement between you and us regarding the App and supersede any prior agreements or understandings. If any provision of these Terms is found to be unenforceable, the remaining provisions will continue in full force and effect.

20. Contact Us

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

• Email: support@nof1.app
• Website: nof1.app