Watch the number climb
The lead number is the time you have spent in daylight today, against a target you pick. It is on the Today screen, both widgets, and every complication.
Apple Health counts the minutes you spent in daylight. This gives that number a target to climb toward, then adds the half nobody shows you: how much the sun still has to offer, and the time you would have to head out to reach it.
See how it worksThe lead number is the time you have spent in daylight today, against a target you pick. It is on the Today screen, both widgets, and every complication.
Short of your target? The app works out the latest you could start and still reach it before the light goes, and moves that time with the season.
Daylight+ checks how recorded daylight lines up with sleep, activity, heart, and breathing records. It highlights only clear relationships and says when none appear.
The app uses the NOAA solar position algorithm and one approximate location fix. There is no server, no background tracking, and no network call to find out when the sun sets. It handles the polar cases too, where the sun does not rise or does not set at all.
Check the remaining figure in a widget or a watch complication, choose which Apple Health sources count, and set a reminder before your daily deadline. Time in Daylight is recorded by Apple Watch; without one, the minutes-spent figure stays at zero and the app says so, while the sunrise and sunset half still works.
The optional Personal Daylight Model reads sleep, activity, resting heart rate, heart-rate variability, and respiratory rate. It runs entirely on your device and never uploads Health data.
Daylight reports what your devices recorded and what the sun offers. Your daily target is your own preference. The app does not diagnose, treat, cure, or prevent anything, and makes no claim about mood, sleep, vitamin D, or eyesight.