Last updated: October 2026

Terms & Conditions — SunSync

These Terms & Conditions govern your use of the SunSync iOS app. By downloading, accessing, or using SunSync, you agree to these terms.

Wellness app
No medical advice
Apple-managed purchases

1. Acceptance of Terms

By using SunSync, you agree to be bound by these Terms & Conditions. If you do not agree, please do not use the app.

These terms apply in addition to Apple's Licensed Application End User License Agreement.

2. Purpose of the App

SunSync is a wellness and lifestyle app designed to help users better understand daily light exposure, routines, and circadian-aligned habits.

The app shows solar times and daylight windows, the UV index, estimated vitamin D from sun sessions, supplements and daylight recorded in Apple Health, sunrise tracking, and reminders aligned with the sun.

SunSync is provided for general informational and self-tracking purposes only.

Important: SunSync does not provide medical advice, diagnosis, treatment, or professional healthcare guidance. Any information, reminders, estimates, or suggestions in the app should not be used as a substitute for advice from a qualified professional.

3. Sun Exposure and Estimates

Vitamin D estimates, recommended session times and the UV index are approximations. They are based on the profile you enter, the position of the sun, weather forecasts and, if you allow it, daylight data from Apple Health, all of which can be incomplete or inaccurate.

Sensitivity to sunlight varies from person to person and can be affected by medication or health conditions. You decide how much sun you get and remain responsible for your own exposure.

4. User Responsibilities

You agree to use SunSync lawfully and responsibly. You are responsible for:

  • the accuracy of any information you enter into the app,
  • your own decisions, routines, and actions based on app content or insights,
  • keeping your device and access credentials secure, where applicable.

5. App Availability and Features

We may update, modify, suspend, or discontinue any feature of SunSync at any time, with or without notice.

We do not guarantee that every feature will always be available, uninterrupted, or error-free.

6. Data and Local Storage

SunSync stores your app data locally on your device in order to provide its functionality. SunSync does not keep a copy of your data on its own servers.

Your data is included in your regular iPhone or iPad backups (iCloud or computer), which you can use to restore it on a new device.

You understand that deleting the app, changing devices without a backup, operating system issues, or device malfunction may result in the loss of locally stored information.

7. Notifications

If you enable reminders or alerts, SunSync may send local notifications to your device.

First light and sunset notifications, and the alert when a sun session reaches its recommended time, are available to all users at no cost. Advanced circadian reminders — including the vitamin D window alert, dinner cutoff, blue-light blocker reminder, bedtime reminder, and screen cutoff — are available exclusively to subscribers.

You can disable notifications at any time through your system settings.

8. Subscription, Purchases, and Billing

SunSync offers an optional premium upgrade that unlocks the following features:

  • Home screen widget
  • Advanced circadian reminders: vitamin D window alert, dinner cutoff, blue-light blocker reminder, bedtime reminder, and screen cutoff

First light and sunset notifications remain free for all users and are not affected by subscription status.

The premium upgrade is available under two options:

  • Annual subscription — auto-renews every year at the price shown in the App Store at the time of purchase. Includes a 3-day free trial for new subscribers.
  • Lifetime purchase — a single one-time payment granting permanent access to all premium features.
Free trial: The annual subscription includes a 3-day free trial. You will not be charged during the trial period. If you do not cancel before the trial ends, the subscription price will be charged to your Apple ID automatically.

All purchases are processed by Apple through the App Store. The following conditions apply:

  • Payment is charged to your Apple ID account upon confirmation of purchase, or — for the annual plan — at the end of the free trial period.
  • Annual subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period.
  • Your account will be charged for renewal within 24 hours prior to the end of the current period at the then-current subscription price.
  • To cancel, go to your Apple ID account settings in the App Store. Cancellation takes effect at the end of the current billing period.
  • Refunds are handled by Apple in accordance with their policies. We do not process refunds directly.
  • We do not have access to or store your payment card details.

9. Third-Party Services

Some features rely on services provided by third parties, including Apple Health, Apple Weather (WeatherKit) and RevenueCat. Your use of these features is also subject to their own terms and policies.

SunSync does not control these services and does not guarantee the accuracy, availability or completeness of the data they provide. Weather data is provided by Apple Weather (data sources).

10. Intellectual Property

SunSync, including its design, branding, text, visuals, code, and related content, is owned by the app creator or licensed to the app creator, unless otherwise stated.

You may not copy, reproduce, modify, distribute, resell, or reverse engineer any part of the app except as permitted by applicable law.

11. Prohibited Use

You agree not to use SunSync to:

  • violate applicable laws or regulations,
  • interfere with the app’s normal operation,
  • attempt unauthorized access to systems, code, or services related to the app,
  • misuse, copy, or exploit the app beyond its intended personal use.

12. Disclaimers

SunSync is provided on an as is and as available basis to the maximum extent permitted by law.

We make no warranties or guarantees regarding accuracy, reliability, availability, fitness for a particular purpose, or uninterrupted access.

Nothing in these terms excludes or limits any rights you have as a consumer under applicable law that cannot be excluded or limited by contract.

13. Limitation of Liability

To the maximum extent permitted by law, we are not liable for any indirect, incidental, special, consequential, or punitive damages, or for any loss of data, profits, business, health-related outcomes, or goodwill arising from your use of, or inability to use, SunSync.

This does not limit liability that cannot be limited by law, including liability for intentional misconduct or gross negligence.

14. Changes to These Terms

We may update these Terms & Conditions from time to time. Continued use of SunSync after updated terms become effective constitutes acceptance of the revised terms.

15. Governing Law

These Terms & Conditions are governed by the laws of Spain. Any dispute arising from or related to these Terms shall be submitted to the courts of Bilbao, Bizkaia, Spain, unless otherwise required by mandatory consumer protection law.

16. Contact

If you have any questions about these Terms & Conditions, you can contact:

Email: sunsyncapp@gmail.com