Support
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Get in touch
support@meridiemsun.comFrequently asked
Meridiem isn't recording my sun time.
Meridiem relies on Apple Watch "Time in Daylight" data and your location. Make sure your Apple Watch is paired and worn, and that you granted Meridiem access to Health and Location. You can check in Settings → Privacy & Security → Health and → Location Services. Data can take 15–60 minutes to arrive from the watch in the background.
How does it know my limit?
During setup Meridiem learns your skin type and builds your personal sun limit (your MED). Over time it adapts as you tan, recover from heavy days, or tell it about sun-sensitising medication.
The UV index looks wrong.
UV data comes from Apple WeatherKit for your current location. Ensure Location Services are on and you have a network connection so Meridiem can refresh the forecast. Elevation and cloud cover can also affect the reading.
Will it sync between my iPhone and Apple Watch?
Yes. Your profile and history sync through your own private iCloud, and the watch and iPhone stay in step over their direct connection. Make sure both devices are signed in to the same Apple Account with iCloud enabled.
How do I delete my data?
Everything lives on your device and in your private iCloud. Deleting the app removes its on-device data; you can manage synced data under Settings → [your name] → iCloud. We hold no data about you on any server.
Is Meridiem a medical device?
No. Meridiem provides estimates to support everyday sun-safety decisions. It can't detect sunburn or replace professional advice. Always use sunscreen, cover, and shade, and consult a professional for any health concern. See the Terms of Use.