Night view
Start with duration and stage estimates.
Review time asleep and the available Awake, REM, Core, and Deep segments contributed by Apple Health sources.
Sleep and recovery
Turn nights of sleep data into a pattern you can understand.
Metric organizes sleep data available through Apple Health into views for duration, stages, consistency, and recovery context. Use it to compare nights and longer trends, then look for repeatable patterns around training and daily habits. Wearable sleep data is an estimate, so trends are usually more useful than one night.
- Sleep duration and stages
- Bedtime consistency
- Training and recovery context
The useful answer
The goal is not to win one night. It is to understand the repeatable pattern.
Metric reads the sleep history you permit through Apple Health and gives night-level detail a longer time horizon. Duration, stage estimates, timing, and consistency can be reviewed without treating any one measure as the whole story.
The useful question is often comparative: what changed before better nights, what repeats before shorter nights, and whether the pattern persists long enough to deserve attention.
Inside Metric
Designed to keep the context attached.
Every summary should lead back to the signal, date range, or source that shaped it.
Consistency
Track timing across weeks, not just totals.
Bedtime and wake-time regularity add context that a single duration number can miss.
Recovery context
Place sleep beside the work around it.
Compare the sleep trend with training and other available signals without assuming that a visual relationship proves cause.
How it works
Three steps from data to a better question.
Enable a sleep source
Set up Apple Watch sleep tracking or another compatible Health source and allow Metric to read sleep data.
Collect repeat nights
Wear the device consistently enough to separate a pattern from an isolated night.
Compare like with like
Review similar weekdays, training periods, and routines before drawing a conclusion.
What to know first
Useful, with clear limits.
- Consumer wearables estimate sleep and stages; they are not the same as a laboratory sleep study.
- Missing wear time, battery loss, schedule settings, and source priority can create gaps or change the displayed history.
- A correlation between sleep and another trend in the app does not establish what caused either change.
A good fit if
- You already collect sleep data through Apple Watch or Apple Health.
- You care about duration and regularity, not only a daily score.
- You want sleep near your workout and recovery context.
Probably not for you if
- You need diagnosis or treatment for a sleep disorder.
- You cannot wear or use a compatible sleep source consistently.
- You want one night’s stage estimate treated as a definitive result.
Common questions
The short version.
Does Metric record sleep itself?
Metric uses sleep samples available through Apple Health. The contributing device or app must record the data and you must permit access.
Why is a night missing?
Common reasons include no source sample, disabled access, insufficient wear time, a depleted Watch battery, or Health source-priority changes.
Should I focus on stages or duration?
Both can provide context, but wearable stages are estimates. Longer patterns in duration, timing, and consistency are generally easier to interpret than one stage reading.
Sources and context
Read the primary material.
Official platform documentation and original research are linked for context, not used to overstate what one app view can conclude.
Apple Support
Track your sleep on Apple Watch and use Sleep on iPhone
Official setup and interpretation guidance for Apple Watch sleep duration, stages, consistency, and source limitations.
Apple Developer
Authorizing access to health data
Official documentation for HealthKit’s category-by-category read and write permissions, including limited-history access.
Sleep / PubMed
Sleep regularity is a stronger predictor of mortality risk than sleep duration
A prospective cohort study using objective sleep-wake measurements; it supports looking at regularity as a trend while not establishing cause for an individual.
Metric for iPhone
Make your health history easier to use.
Connect only the categories you choose. Start with the dashboard, then go deeper when a trend earns your attention.
Download on theApp Store