Healthy Weather: Vitamin D

Your live vitamin D₃ tracker & UV guide — now fully on-device and private. Watch your skin make vitamin D in real time and plan your sun. Powered by Apple Weather.

Healthy Weather: Your Daily Sun & Vitamin D Guide

Healthy Weather turns sunlight into something you can actually plan around. See exactly when your body can make vitamin D, how strong the UV is, and how much sun you've had — in a clean, science-backed app that runs entirely on your device.

At its heart is a custom Vitamin D Index that models how your skin produces vitamin D₃ from sunlight — using your skin type, age, exposure and live conditions, not a generic chart.

Free Features:

• Today at a glance: your Vitamin D window, sun-risk hours, feels-like and current conditions
• A plain-language daily summary of your sun day
• Tap any tile for an explanation and a mini graph
• Vitamin D Tracker: 5 free sessions to try it out

Premium Features (free 14-day trial):

• Vitamin D Tracker (unlimited): Start a session and watch your skin's vitamin D₃ production in real time — live IU per minute, a running total, and a saturation indicator that tells you when you've had enough sun. Review every past session with detailed Vitamin D Index, UV, synthesis-rate and saturation charts. Built on published science, not guesswork.
• 7-Day Forecast: Day-by-day Vitamin D window, UV, temperature and rain outlook so you can plan your sun ahead
• Detailed Graphs: Vitamin D Index, UV, solar altitude, feels-like and precipitation through the day, with smooth interactive charts
• Ad-Free & Beautiful: A clean, premium interface that puts your health data front and center

Private by design: Everything runs on your device. No account, no sign-up, no analytics — your tracking history never leaves your iPhone. Weather data is provided by Apple Weather.

Subscription Information: Healthy Weather offers a Monthly plan. Payment is charged to your App Store account after the 14-day free trial. The subscription auto-renews unless canceled at least 24 hours before the end of the current period. You can manage or cancel anytime in your Apple ID settings.

Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/