# Rays: Auto Vitamin D Tracking — Auto sun exposure tracking

> Automated vitamin D synthesis tracking based on sun exposure and personal factors. (iPhone/iPad app by Rays Health Technologies LLC.)

- Source: https://appshunter.io/ios/app/rays-auto-vitamin-d-tracking/id6752499967 (this page in markdown: same URL + `.md`)
- Developer: [Rays Health Technologies LLC](https://appshunter.io/developer/1829292925)
- Category: Health & Fitness, Lifestyle
- Price: Free with in-app purchases
- Rating: 4.43/5 from 7 App Store ratings · 4 written reviews indexed
- Age rating: 4+
- Requires: iOS 15.1 · 58 MB
- Languages: English
- Released: 2025-09-18
- Data updated: 2026-09-07
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/rays-auto-vitamin-d-tracking/id6752499967/reviews.md

## What is Rays?

Never Worry About Vitamin D Again
Over 1 billion people are vitamin D deficient, but knowing if you’re getting enough sun shouldn’t be complicated. Rays is the world’s first app that automatically tracks your vitamin D synthesis, so you can spend your time enjoying life. No manual logging, no thinking required.

Why Vitamin D Matters Optimal vitamin D levels support natural energy, balanced mood, healthy sleep cycles, and radiant skin. With Rays’ precise tracking, you can maintain these benefits year-round without guesswork or overdoing it.

Automatic Vitamin D Tracking Rays uses a first-of-its-kind outdoor detection system combining GPS precision patterns, sensor data, movement analysis, and personalized machine learning that adapts to your routines. With high accuracy and minimal battery usage, it works seamlessly in the background without any manual input.

Personalized Health Intelligence Our algorithm analyzes your skin type (Fitzpatrick Scale I-VI), age, geographic location, supplement intake, and lifestyle factors. Based on Endocrine Society Clinical Practice Guidelines, we provide recommendations as precise as your doctor’s, but as convenient as checking the weather.

Smart Recommendations Receive personalized guidance like “Get 18 minutes at 11 AM tomorrow” based on real-time UV index, cloud cover, solar positioning, and your personal synthesis rate. Our intelligent engine suggests optimal timing when UV will be 2-3x more efficient for vitamin D production.

Advanced Progress Tracking Monitor your vitamin D synthesis with detailed weekly charts, streak tracking, and comprehensive health insights. Seamlessly syncs with Apple Health and automatically adjusts for seasonal variations while preventing excessive intake when combined with supplements.

For Tanners & Sun Enthusiasts Already spending time in the sun for a tan? Put that exposure to work. Rays tracks your cumulative UV dose so you can optimize your color, avoid overexposure, and know exactly where you stand — all automatically.
Rays is perfect for health-conscious individuals who want optimal vitamin D without the guesswork.

Try Rays free for 3 days with full access to all features.

Terms of Use: https://getrays.app/eula
Privacy Policy: https://getrays.app/privacy
Health Disclaimer: https://getrays.app/health-disclaimer

## Key features

- Automatic vitamin D synthesis tracking
- Personalized health intelligence
- Smart sun exposure recommendations
- Progress tracking and health insights
- Apple Health integration
- Minimal battery usage

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Rays - Auto Vitamin D Tracker | $19.99 | per year |
| Rays - Auto Vitamin D Tracker | $4.99 | per month |


## Recent user reviews (4 of 4)

All indexed reviews: https://appshunter.io/ios/app/rays-auto-vitamin-d-tracking/id6752499967/reviews.md

### 1/5 — Doesn’t log

*2026-05-14*

Hit start button does nothing.

**Developer response:** Hey, we're so sorry you were experience this. There was a bug in that release that caused it. It should be resolved in our latest release submission (1.37). If you would like to reset your trial, please email us at team@getraysapp.com and we're happy to help! Hope you see the benefits of Rays.

### 5/5 — Great

*2026-04-15*

This app works so well and nicely laid out, very user friendly and does detect outdoor time auto which is such a nice feature! Also I had a question and emailed them and they replied so quick, they’re the most helpful and responsive I’ve ever seen! So excited to use this summer and the future of this app!

### 5/5 — Game-Changer for daily wellbeing!

*2025-12-12*

I’ve rarely thought about the impact of Vitamin D on my overall daily wellbeing - Rays has made it possible to get the most of my time. It’s simple, informative, and clean UI have led to major improvements in my overall happiness!

### 5/5 — 5 star

*2025-12-12*

I wish I had started tracking my Vitamin D levels sooner. I’m already seeing an improvement in energy thanks to Rays.

## Frequently asked questions about Rays

### Does Rays have ads?

No, Rays does not contain advertisements. It is designed to provide a seamless and uninterrupted user experience focused on your health.

### How does Rays track vitamin D automatically?

Rays uses a combination of GPS, sensor data, movement analysis, and machine learning to detect outdoor exposure. It then analyzes your skin type, age, location, and lifestyle to estimate vitamin D synthesis without manual logging.

### What are the subscription options for Rays?

Rays offers a 7-day free trial for all features. After the trial, subscriptions are available at $4.99 per month or $19.99 per year.

### Can Rays sync with other health apps?

Yes, Rays seamlessly syncs with Apple Health. This allows for a more comprehensive view of your health data and automatically adjusts for seasonal variations.

### What kind of recommendations does Rays provide?

Rays provides personalized guidance, such as suggesting optimal times and durations for sun exposure based on real-time UV index, cloud cover, and your individual synthesis rate.

### Is Rays suitable for all skin types?

Yes, Rays' algorithm analyzes your skin type on the Fitzpatrick Scale (I-VI) to provide precise recommendations tailored to your individual needs and sun sensitivity.

### How often is Rays updated?

The latest version of Rays is 1.30, and it was last updated on March 17, 2026. Updates typically focus on improving tracking accuracy, personalization algorithms, and user experience.

### What devices does Rays support?

Rays is available for iPhone and iPod devices. It is designed for users who want to monitor their vitamin D levels conveniently on their Apple mobile devices.

## Version history (last 5 releases)

### 1.45 — 2026-08-28

- Bug fixes

### 1.44 — 2026-07-15

- Bug fixes

### 1.43 — 2026-07-06

- Update scoring modal
- Bug fixes

### 1.42 — 2026-06-26

- Updates to Insights
- Bug fixes

### 1.41 — 2026-05-27

- Bug fixes

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| --- | --- | --- | --- |
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| [My Endorphin](https://appshunter.io/ios/app/my-endorphin/id1067389642) | 4.5 (6) | Free | Health & Fitness |
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## More apps by Rays Health Technologies LLC

- [TalkJournal: Voice Diary](https://appshunter.io/ios/app/talkjournal-voice-diary/id6758567103)

All apps by Rays Health Technologies LLC: https://appshunter.io/developer/1829292925

## Related topics

[vitamin d sun tracker](https://appshunter.io/ios/topics/vitamin-d-sun-tracker) · [vitamin d sun](https://appshunter.io/ios/topics/vitamin-d-sun) · [free vitamin d tracker](https://appshunter.io/ios/topics/free-vitamin-d-tracker) · [vitamin d tracker](https://appshunter.io/ios/topics/vitamin-d-tracker) · [vitamind app](https://appshunter.io/ios/topics/vitamind-app) · [sun rays](https://appshunter.io/ios/topics/sun-rays) · [rays](https://appshunter.io/ios/topics/rays) · [vitamin d](https://appshunter.io/ios/topics/vitamin-d)

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*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 2026-09-07.*