UV Guard

Problem

Most people reapply sunscreen based on guesswork or simply forget. Existing reminders are time-based and generic: they ignore the actual UV intensity at your location, your skin type, the SPF you're using, and whether you're swimming or playing sport. The result is a false sense of protection.

Approach

Built a native Garmin Connect IQ app that pulls live UV index data from Open-Meteo using the watch's GPS coordinates. A scientifically-grounded formula combines UV index, skin type (I–VI), and SPF to calculate the real protection window, with a realistic effective-SPF adjustment for under-application. Activity mode (dry, sweating, swimming) further reduces the timer for high-risk scenarios. A color-coded arc (green to purple) shows UV severity at a glance, and a single button press logs a reapplication and resets the countdown.

Outcome

A complete sun-safety tool that runs on the wrist with no phone interaction. Live on the Garmin Connect IQ Store.