Name: SunAlert: UV, Burn & Vitamin D
Rating: 4.9 (22 reviews)
Author: roey_bretschneider

Stay safe and get the most out of your time outdoors with SunAlert.

IMPORTANT DISCLAIMER:
SunAlert is for informational purposes only. Results are mathematical estimates and are not a substitute for professional medical advice or standard sun safety practices. Variables such as altitude, reflective surfaces (water, sand, snow), and individual skin conditions can significantly affect actual burn times. Always use sunscreen and follow medical guidelines for sun protection.

SunAlert tells you exactly how long you have before your skin starts burning — and now tracks your daily Vitamin D exposure too. By combining the current UV Index with your Fitzpatrick Skin Type, the app gives you a personalized window for healthy sun exposure: enough UV to synthesize Vitamin D, not so much that you burn.

Key Features:

Automatic UV Sync: Fetches real-time UV Index data directly to your Garmin watch via Garmin Weather services.

Vitamin D Tracking: A dedicated screen tracks your daily UV dose toward your Vitamin D target (25% of your skin's MED). See minutes remaining at the current UV level and a Mon–Sun weekly streak showing days you hit your target. Dose accumulates across sessions and survives session resets — only a new day resets it.

Personalized for Your Skin: Choose from all six Fitzpatrick skin types — Very Fair to Dark — for tailored burn time and Vitamin D estimates.

Tanning Threshold Monitor: Identifies the window where healthy melanin production begins (50% of MED) before UV damage occurs.

Background Alerts: Receive a notification when you enter the tanning zone and a second alert when you reach your burn limit — even when the app is closed.

Smarter Burn Countdown: Remaining time reflects the UV dose already accumulated during your session, not just the current UV level.

Glanceable Widget: Quick-look timer showing minutes to tan and minutes to burn, always visible in your watch's widget loop.

The Science:
SunAlert uses your Minimal Erythema Dose (MED) and current UV intensity to calculate when your accumulated dose reaches the Vitamin D synthesis zone (25% MED) and your personal burn threshold (100% MED).

---What's New
Version 1.6.1
UV Today forecast screen, Weekly sun exposure in SED, "Tan" is now called "Damage" + new "?" explainer, Snow & Beach now count reflected UV, Seasonal icon, Fixed sessions starting on their own

Version 1.5.0
settings added and much more

Version 1.4.2
Pause & Resume , Altitude UV Correction, Small bug fixes
credit to Gal for the Pause & Resume

Version 1.4.0

Add button support!

Smoother SPF selection — Choosing an SPF value returns directly to the main screen with no brief flash of the activity list.

Expanded device support — 82 supported devices, all confirmed glance-capable.

Version 1.3.0
major update, support SPF sunscreen and some activites

Version 1.2.0

Vitamin D tracking screen — swipe up from the main view to see your daily UV dose progress, minutes remaining to hit your Vit D target, and a Mon–Sun weekly streak.

Tappable skin type button — tap the skin indicator in the main view header to change your skin type directly.

Version 1.1.0

Background notifications for tan zone and burn limit alerts.

Smarter burn countdown using accumulated UV dose across the full session.

One-time safety disclaimer on first launch.

Bug fixes: session reset behavior, UV=0