Find out what affects your sleep, energy and mood
It can show what tends to move together in your own data, such as short nights and low afternoon energy, but it cannot prove cause. Daylumen puts Apple Health sleep and activity, optional weather, calendar load (counts and hours only, never titles) and your own check-ins on one timeline and says how sure it is.
You already suspect that a late night, a bad forecast or a packed calendar changes how your day goes. Daylumen lines those things up so you can check the hunch against your own history.
The question behind the app
Most trackers report numbers. The question people actually ask is different: why did I feel flat on Tuesday, and does it keep happening after short nights? That needs several kinds of data in one place, compared with your own normal.
What goes on the timeline
- Sleep and activity from Apple Health: sleep entries, steps, exercise time and, when available, resting heart rate and heart rate variability.
- Weather for each day, looked up through Apple WeatherKit with a coarse location. Optional.
- Calendar load: how many timed events and how many busy hours. Event titles are never read. Optional.
- Your own check-in: mood, energy and stress on a quick scale, a few state or event tags, a note. Takes seconds.
How the pattern shows up
Daylumen compares each day with your personal baseline, meaning your own usual range rather than a population average. When two things keep moving together, for example shorter sleep and lower afternoon energy, it points that out and says how sure it is. When the evidence is weak it says that instead of guessing.
The Atlas screen lists every dimension Daylumen can read, how many days of data each has and where it comes from, so you can see what the app is basing a statement on.
A realistic example
Suppose you log your energy for three weeks. Daylumen may notice that your afternoon energy is lower after nights where you slept clearly less than your usual, and higher on days with a longer walk. That is a pattern in your data, not a cause proven by an experiment, and the app phrases it that way.
Keep it light
Nothing has to be filled in daily. The check-in is optional, and the morning message, if you switch it on, shows up at most once a day and only when there is something worth knowing.
Frequently asked questions
Can Daylumen tell me what causes my poor sleep?
It can show what tends to move together with your sleep in your own data, such as activity, weather or a busy calendar. It cannot prove cause, and it does not diagnose sleep problems.
How many days of data does it need?
It starts reading from what is already in Apple Health. The Atlas screen shows how many days each dimension has, and Daylumen says when a signal is too thin to read.
Does it read my calendar event titles?
No. Only the count and total length of timed events are used. Titles, notes, attendees and locations are never read.
Daylumen reads the health data already on your iPhone and tells you what it means for today.
Get Daylumen on the App StoreFree to download · iPhone · iOS 17 or later · a one-time in-app purchase unlocks the deeper tools