# Light by The Circadian Bros — Circadian Rhythm, UV & Sleep > Personalized light exposure plan for circadian rhythm and vitamin D optimization. (iPhone/iPad app by The Circadian Bros, LLC.) - Source: https://appshunter.io/ios/app/light-by-the-circadian-bros/id6789722310 (this page in markdown: same URL + `.md`) - Developer: [The Circadian Bros, LLC](https://appshunter.io/developer/6776371538) - Category: Health & Fitness, Lifestyle - Price: Free with in-app purchases - Rating: 5.00/5 from 9 App Store ratings · 4 written reviews indexed - Age rating: 4+ - Requires: iOS 15.1 · 86 MB - Languages: American English - Released: 2026-10-23 - Data updated: 2026-11-06 - Monetization: subscription - User reviews in markdown: https://appshunter.io/ios/app/light-by-the-circadian-bros/id6789722310/reviews.md ## What is Light by The Circadian Bros? Tired all day and wired at night? Your body clock runs on light, and most of us get it at the wrong times. Light gives you a simple daily plan to fix that, with a little help from Buddy the sun and Luna the moon. Every morning, Light builds your day around your sunrise, the UV forecast where you are, your skin type and the time you actually have. You get a trail of light sessions from sunrise to sunset: when to go out, how long to stay, and whether it should be direct sun or shade. WHAT YOU GET • Your daily light plan: morning light, vitamin D windows and evening light, timed to your sunrise and today's UV • Buddy, your light coach: tap play, pick sun, shade or mixed, and step outside • Live sessions with a timer sized to your skin and the UV right now, so you know when to head inside • Estimated vitamin D as it adds up, based on your skin type and what you're wearing • Live Activity and Dynamic Island, so your session stays on your Lock Screen • Forgot your phone? Log time you spent outside earlier in the day • Sleep from Apple Health, side by side with the light you got • A spectral breakdown of the light around you: UV-B, UV-A, visible light and infrared • Streaks with freezes, and ranks from Bronze to Circadian Legend • Luna takes over at sunset to help you wind down • Buddy's Journal: short, science-backed reads on light, sleep and vitamin D • Friends, so you can keep each other going HOW IT WORKS A short setup asks about your mornings, your sleep, your skin and your goals. From there, Light reads the forecast for your location and places your sessions where they do the most: morning and evening light for your body clock, and vitamin D windows only when the UV is high enough to matter. On low-UV days the plan stays honest and gives you a shorter day. After sunset, new sessions pause until sunrise. That's by design: nights are for darkness and sleep. SUBSCRIPTION Light is a subscription app, with monthly and yearly plans. The yearly plan starts with a 7-day free trial for eligible new subscribers. Payment is charged to your Apple Account when you confirm your purchase or when the free trial ends. Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period. Manage or cancel anytime in your Apple Account settings. ABOUT THE NUMBERS Vitamin D figures are estimates, modeled from UV data, your skin type, skin exposure and time. They are not a measurement of vitamin D in your blood. Light is not a medical device and is not a substitute for medical advice. Session lengths are based on your skin type and current conditions, but no app can predict exactly how your skin will respond, so use your own judgment and avoid sunburn. Made by two brothers who believe light is health. Terms of Use: https://thecircadianbros.com/policies/terms-of-service Privacy Policy: https://thecircadianbros.com/policies/privacy-policy ## Key features - Daily light plan based on sunrise and UV forecast - Personalized sun and shade session guidance - Estimated vitamin D tracking - Live Activity and Dynamic Island integration - Ability to log past outdoor time - Spectral light breakdown (UV-B, UV-A, visible, infrared) - Sleep tracking integration with Apple Health ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | Premium Monthly | $6.99 | per month | | Premium Yearly | $39.99 | per year | ## Is Light by The Circadian Bros safe? Not enough ratings yet to assess Light by The Circadian Bros. ## Is Light by The Circadian Bros legit? Light by The Circadian Bros has limited verification signals. The AppsHunter Legitimacy Score for Light by The Circadian Bros is 58 out of 100 points across 7 verification signals from App Store and developer data. ## Recent user reviews (4 of 4) All indexed reviews: https://appshunter.io/ios/app/light-by-the-circadian-bros/id6789722310/reviews.md ### 5/5 — Necessary app for being healthy *2026-10-27* The sun is healing! This app helps me stay on top of my focus and tan. It’s free, and I’d recommend it to everyone serious about health habits. ### 5/5 — Highly recommend *2026-10-24* This app helps you get sun exposure the right way couldn’t recommend enough ### 5/5 — Go Get Some Sun *2026-10-23* An amazing app! The interface is intuitive, and I love how it recommends exposure time based on my skin’s sensitivity to the sun. It also updates my planned time in the sun based on my location, the time of day, the weather, and my skin, making everything feel tailored to me. It’s helping me plan healthier sun exposure throughout the day to boost my vitamin D, and to improve my sleep and overall health. This will be a great tool to use at home or when traveling for work. Highly recommend! ### 5/5 — Great app *2026-10-23* The app is well designed and ensures the user is getting safe sun exposure. The reminders are great for someone with a busy schedule who forgets to take breaks outside. And there are a lot of neat features like the research, lux, and wavelengths chart when you tap on the sun. ## Frequently asked questions about Light by The Circadian Bros ### What is Light's subscription cost? Light offers a Premium Monthly plan for $6.99 and a Premium Yearly plan for $39.99. The yearly plan includes a 7-day free trial for eligible new subscribers. ### How does Light help with my body clock? Light creates a daily plan based on your sunrise, UV forecast, and skin type. It guides you on when to get morning light, vitamin D windows, and evening light to align with your natural circadian rhythm. ### Can I manage my Light subscription? Yes, subscriptions renew automatically unless canceled at least 24 hours before the current period ends. You can manage or cancel your subscription anytime in your Apple Account settings. ### Does Light track vitamin D accurately? Light provides estimated vitamin D figures based on UV data, your skin type, and exposure. These are not blood measurements, and the app is not a medical device. Always use your own judgment to avoid sunburn. ### What devices does Light support? Light is available for iPhone and iPod devices, as indicated by its compatibility. ### How often is Light updated? The app was last updated on November 5, 2026, with version 1.02, suggesting regular updates to improve functionality and features. ### What age rating does Light have? Light has an age rating of 4+, making it suitable for a wide range of users interested in health and wellness. ### Does Light have ads? No, Light does not contain advertisements. It is a subscription-based application, ensuring an ad-free user experience. ## Version history (last 3 releases) ### 1.02 — 2026-11-05 Meet Light, by The Circadian Bros! - A whole new look: calmer, brighter, easier to use - Buddy guides your day, and Luna takes over at night - A new Plan trail that shows your light sessions from sunrise to sunset - Log time outside you forgot to track - Mix-and-match outfits for more accurate sun estimates - Existing members: enjoy a free month of full access, on us - Try it free for 7 days with the yearly plan - Smarter re-planning, offline saving, and lots of fixes ### 1.01 — 2026-10-29 Meet the new TheCircadianBros App, with a fresh look and a calmer, smarter way to get your daily light. NEW - Your Rank: see how your sunlight habits add up (consistency, morning light, sleep, sun safety and more) and compare with friends. - The Moon: after sunset the moon rises on your Home screen with its real phase. Premium members can tap it for tonight's moon reading. - Time you didn't log (Premium): with Apple Health, your end-of-day review finds walks and outdoor time you forgot to track. Confirm what looks right and it counts toward your day. - Sessions no longer end on their own. Stayed out longer? Tell us and the extra time counts. - Winter-friendly vitamin D: on low-UV days you'll see a realistic target for today, so you can still hit what's possible. - Low UV counts too: direct sun at UV 1–2 now earns a little vitamin D. - New share cards, including one for your sleep. IMPROVED - A redesigned Friends page: add friends from one simple button, see when cheers arrived, and get a dot when there's something new. - Home fits smaller phones and larger text sizes. - Clearer Apple Health settings in your Profile. - Better guidance for building your own plan. - A new app icon. FIXED - Rate the App and Friends no longer close the app. - Many smaller fixes and polish. Thank you for getting outside with us. If you enjoy the app, a rating means a lot. ### 1.0 — 2026-10-23 No release notes. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-11-06.*