Opsin: Circadian Sun & Sleep
Opsin App LLC Health & Fitness iPhoneiPadiPod touch
Opsin: Circadian Sun & Sleep is a free Health & Fitness app for iPhone and iPad by Opsin App LLC. Rated 4.2/5 from 5 ratings. Requires iOS 18.0.
- Rating
- 4.2
- 5 ratings
- Price
- Free
- on the App Store
- Size
- 5 MB
- Age 4+
- Updated
- Sep 26
- 2026 · v1.4
Screenshots
About Opsin: Circadian Sun & Sleep
Opsin syncs your day with the sun. Most health apps hand you more numbers. Opsin does the opposite — it tells you the one thing to do for your circadian rhythm right now, then shows you it worked in your own sleep and recovery. Light sets your body clock. Opsin sets your light. WHAT OPSIN DOES - Live sun times and your daily light windows — morning light, vitamin D window, blue hour, and bedtime, calculated for your exact location and updated automatically all year. - A real, dynamic dawn alarm — recalculates to civil dawn every night, so you wake into the light without ever resetting a thing. - See what morning light does to you — Opsin reads your sleep and HRV from Apple Health and reflects the difference light makes in your own body. - Jet-lag plans with exact clock times — shift your body clock before you fly, so you land already adjusted. - Your lights, automatically on sun time — optional HomeKit support. WHY IT MATTERS A regulated circadian rhythm is the foundation under sleep, energy, and mood. Instead of highlighting downstream problems, Opsin addresses the behavior at the root — and makes it effortless. PRIVATE BY DESIGN No account. No backend. Your health and location data are processed entirely on your device and never leave your phone. SUBSCRIPTION Opsin Premium unlocks every feature. $9.99/month or $79/year, each with a 7-day free trial. Payment is charged to your Apple ID; subscriptions renew automatically unless canceled at least 24 hours before the period ends. Manage or cancel anytime in your App Store settings. Opsin is a general wellness and educational tool. It is not a medical device and does not diagnose, treat, or prevent any condition. Consult a qualified professional for medical concerns. Scripture quotations taken from the New American Standard Bible® (NASB), Copyright © 1960, 1971, 1977, 1995 by The Lockman Foundation. Used by permission. www.Lockman.org Terms of Use: https://opsinapp.com/terms Privacy Policy: https://opsinapp.com/privacy
Ratings & reviews
4.2
5 ratings
What’s new
Version 1.4 · Updated September 26, 2026
Opsin now works anywhere on Earth. • Weather and UV wherever you are. Outside the US, Opsin now uses Apple Weather for live conditions and UV, so your vitamin D window and sun guidance stay accurate abroad. • Travel-aware. Land in a new time zone and Opsin retimes your sun windows, alarms, and meal window automatically. • Built for extreme latitudes. Under the midnight sun or in polar night, Opsin switches to honest, clock-anchored guidance instead of going blank. • Stability and accuracy improvements.
App privacy
The developer, Opsin App LLC, reported these privacy practices to Apple.
Data Not Collected
The developer does not collect any data from this app.
Alternatives to Opsin: Circadian Sun & Sleep
Looking for apps like Opsin: Circadian Sun & Sleep? Here are 6 similar apps on the App Store. The highest rated is MyCircadianApp (4.9/5), and all 6 are free to download.
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Sunrise Alarm Clock -
4.0
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Glow Alarm - Wake Up Light
4.3
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MyCircadianApp
4.9
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Circadian: Your Natural Rhythm
4.6
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D Minder Pro
4.0
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MyMojoHealth
4.7
| App | Rating | Price | Last updated | Compare |
|---|---|---|---|---|
| Opsin: Circadian Sun & Sleep | 4.2 / 5 (5 ratings) | Free | September 26, 2026 | |
| Sunrise Alarm Clock - | 4.0 / 5 (39) | Free | Sep 10, 2026 | Compare |
| Glow Alarm - Wake Up Light | 4.3 / 5 (38) | Free | Sep 1, 2026 | Compare |
| MyCircadianApp | 4.9 / 5 (265) | Free | Oct 1, 2026 | Compare |
| Circadian: Your Natural Rhythm | 4.6 / 5 (667) | Free | Jun 14, 2026 | Compare |
| D Minder Pro | 4.0 / 5 (1,795) | Free | Oct 16, 2026 | Compare |
| MyMojoHealth | 4.7 / 5 (18,846) | Free | Oct 16, 2026 | Compare |