Free

Sun Sessions

Track time in the sun from your iPhone, with or without an Apple Watch.

How it works

Start a Sun Session when you head outside, and end it when you come back in. Sessions only count daylight hours. When you end one, it's saved to Apple Health as Time in Daylight, so it counts toward your goal, your streak and your history, just like time your watch records. With Sun Exposure Pro and location turned on, the session saves a vitamin D estimate to Apple Health too.

It's how Sun Exposure works without an Apple Watch. With a watch, sessions are handy for marking a specific stretch outside, like a day at the beach.

Start it your way

  • The sun button at the top of the Today tab.
  • The Sun Session control in Control Center.
  • Siri: “Start sun session in Sun Exposure” or “I'm going outside in Sun Exposure”.
  • The Shortcuts app, for your own automations.

While it runs, the session shows as a Live Activity on your Lock Screen and in the Dynamic Island, where you can pause, resume or end it. Say “End sun session in Sun Exposure” when you head back in.

Tell it what you're wearing

Pick your skin coverage when you start, from full coverage to a swimsuit. Sun Exposure uses it, with your skin type, to estimate the vitamin D you made.

Your session history

Every session is listed under Sun Sessions in the History tab, with its own detail screen. Sessions sync between your devices through your iCloud account, and they show up in Spotlight search on your iPhone.

What you need

  • An iPhone with iOS 18 or later. Sessions run on iPhone; Apple Watch tracks automatically instead.
  • Your skin type, set in Settings › Skin & Health before your first session.
  • Permission to save to Apple Health.
  • Location, so sessions only count daylight hours. Approximate location is enough.

Sun Sessions are free. Vitamin D estimates for sessions are part of Sun Exposure Pro.

Questions about Sun Sessions

Can I use Sun Exposure without an Apple Watch?

Yes. Start a Sun Session on your iPhone when you head outside, and end it when you come back in. Sessions only count daylight hours, and when you end one it's saved to Apple Health as Time in Daylight, with a vitamin D estimate if you have Sun Exposure Pro.

Start a session with the sun button at the top of the Today tab, from Control Center, or with Siri, then pause or end it from the Lock Screen. You'll need to set your skin type first.

Can I use Siri and Shortcuts?

Yes. Ask Siri things like "How much sun have I gotten in Sun Exposure" or "What's the UV index in Sun Exposure". On iPhone, you can also start, pause and end a Sun Session with Siri, and every action is available in the Shortcuts app.

What does Sun Exposure store in iCloud?

Your settings, your Sun Sessions (including where they took place), and a summary of your recent sun exposure and last known location are kept in your iCloud account so they stay in sync across your devices. Only devices signed in to your Apple Account can read them, not the developer of Sun Exposure. Apple encrypts this data in transit and on its servers, though unlike your Health data it isn't end-to-end encrypted.

The Time in Daylight and vitamin D records themselves are stored in Apple Health, which end-to-end encrypts them when it syncs with iCloud. To keep Sun Exposure's data out of iCloud, turn off Sun Exposure in the Settings app under your name > iCloud.

Start Your Sun-Smart Journey Today

Free on the App Store for iPhone and Apple Watch.

Download on the App Store

iPhone with iOS 18 or later. Automatic tracking needs an Apple Watch with watchOS 10 or later.

Disclaimer: Sun Exposure gives estimates, not medical advice. Consult your doctor to determine the right amount of sun exposure for you. Always use sunscreen, hats, and shade as needed.