Follow your estimated sun exposure, check UV forecasts and keep track of your sunscreen timer on your Garmin watch. HELIO offers an English and French interface, a seven-day history and tracking alerts while the app is open. YOUR DAILY REFERENCE A large forecast UV index and a chart to explore the day. A percentage and progress arc for your daily reference. Alerts configured for 25%, 50%, 75% and 100%, when alerts are enabled. If several levels are crossed between readings, HELIO selects the highest. An independent timer: select “Sunscreen applied,” choose SPF 30 or SPF 50 and set your reminder interval. UNDERSTANDING THE PERCENTAGE This score is HELIO’s own theoretical reference. Progress depends on counted time, UV forecasts and the selected profile or recorded SPF. For example, 32% means 32% of the daily reference defined by the app, not remaining protection. The counter can exceed 100%. Accumulation requires two successive positive Solar readings close enough together. A zero or unavailable signal, or a long gap, prevents accumulation for that interval. A stronger Solar signal does not directly speed up progress. Solar measures the watch’s charging efficiency, not UV reaching your skin. HELIO reads it approximately every five seconds while active and requests background runs every five minutes while closed, controlled by Garmin. This intermittent tracking cannot reconstruct movements between sun and shade. ALERTS AND REMINDERS The sunscreen reminder is independent of UV and the Solar signal. Settings include tests and an alert-status screen. COMPATIBILITY AND DATA Tracking requires a Solar watch in the compatible-device list. Instinct Solar is not supported in this release. Some Garmin profiles also include non-Solar variants, whose exposure counter cannot function. Forecasts are supplied by Garmin; configure and sync Garmin Connect to keep them updated. Missing or outdated data may pause the calculation. No HELIO account or personal weather API key is required. HELIO stores its records on your watch, with no HELIO server, advertising or external analytics. Permission is requested at first launch. The “Local data” menu lets you review the information and erase records, including archives from earlier versions. A THEORETICAL REFERENCE This percentage is neither a measured UV dose nor a medical threshold. 100% is not a boundary between safe and harmful exposure. The recorded SPF and timer do not measure sunscreen effectiveness or remaining protection. HELIO does not replace sun-protection instructions.