Vitamin D

Track sunlight, UV, and your vitamin D โ€” in real time.

What it does

Your body makes vitamin D from sunshine. Vitamin D reads the live UV index for your location and estimates how much vitamin D your skin is producing, personalized to your skin type, clothing, SPF, and age.

Support

Questions, bugs, or feedback? Email me directly โ€” I read every message.

Common questions

Why does it need my location?
Only to look up the UV index where you are. Coordinates go to the Open-Meteo weather service and are never stored.
Is my health data safe?
Yes. Health data stays in Apple Health on your device and is never sent anywhere.
Is this medical advice?
No. Vitamin D is a wellness and educational tool, and its estimates are approximations. Talk to your doctor about sun exposure or supplements.
Does it cost anything?
The app is free, with no ads and no tracking.