Day's Sleep is the heart of the FitRest Sleep tab. It shows how long you were in bed, how much of that time you actually slept, and how your night moved through Deep, REM, Core and Awake. Every session, from the main night to a short afternoon nap, gets its own breakdown.
The Day's Sleep card opens with two numbers that are easy to confuse: Time in Bed and Sleep Time. Time in bed is the whole window from lying down to getting up. Sleep time is what is left once the awake stretches are taken out. FitRest shows both side by side, along with a quality bar for the night, so you can see at a glance whether a long night in bed was also a long night of sleep.
Below that is a Sleep Sessions list. Each session carries a label, Main Sleep, Extended Nap, Nap or Rest, with its start and end time, its time in bed and its actual sleep. Tap through to the Sleep Analysis screen and FitRest lays the night out in full: a summary header, a plain breakdown of time in bed minus awake time equals actual sleep, your Sleep score with a comparison against your recent average, and a Sleep Architecture view of each stage.
Open any session and you get Session Detail. Its Sleep Hypnogram draws the night as a stepped chart across Awake, REM, Core and Deep. Drag a finger across it to read exactly which stage you were in at any moment, and to see how the cycles repeated through the night.
Under the hypnogram, the heart rate chart colours your overnight heart rate by the stage it was recorded in and sits it on top of a stage ribbon, with a dashed line for your daytime resting heart rate as a reference. You get your lowest, average and highest heart rate for the session and your average heart rate in each sleep stage. Session Detail also includes heart rate variability, blood oxygen and respiratory rate for that session, plus a Sleep Stage Details guide explaining each stage.
Real sleep is rarely one tidy block. FitRest picks one Main Sleep for each day and labels the rest as an Extended Nap, a Nap or Rest. When a day has more than one session, the header adds up the time in bed, lists every session, and places Awake pills between them so you can see the gaps. Each session in Session Detail shows where it sits, for example 2 of 3.
A night is filed under the morning you woke up, so the sleep you get on Friday night counts towards Saturday. If you sleep during the day, for example after a night shift, that sleep stays on the day it happened. And if more than one app or device records the same night, FitRest uses one source for that night so nothing is counted twice.
Sleep is when the body does much of its repair work. Deep sleep is linked with physical recovery, REM sleep with memory and mood, and the total amount of sleep affects energy, focus, appetite and how well you handle training the next day. Most people only notice sleep when it goes badly, and by then a short week has often already added up.
Looking at the same few numbers each morning turns a vague feeling of being tired into something you can act on. You can see whether a late night cost you deep sleep, whether a nap helped or just pushed your bedtime back, and whether a night that felt restless actually was. Over weeks, those small observations are what help you build habits that make your nights better.
FitRest reads sleep from Apple Health. Sleep stages and the overnight heart rate chart need an Apple Watch, or another device or app that saves sleep stages to Apple Health, worn to bed. If you only use the iPhone Sleep Schedule, FitRest still shows your time in bed, and hides the numbers that depend on time actually asleep rather than guessing them.
Yes. When your Apple Watch records sleep stages to Apple Health, FitRest shows Deep, REM, Core and Awake for each night, with durations, percentages and a hypnogram you can scrub through.
Yes. Each day has one Main Sleep, and any other sessions are labelled Extended Nap, Nap or Rest, each with its own time in bed and actual sleep.
Time in bed includes the time you spent awake, such as falling asleep or brief wake-ups. FitRest subtracts the awake time to give your actual sleep.
Yes. Tap the Calendar button at the top of the Sleep tab and pick any day. The whole tab, including Session Detail, follows the day you choose.
FitRest uses one source for each night, so the same sleep is never counted twice.
A 0-100 score for each night's sleep, with a label, a comparison with your recent average and the factor that held it back.
Respiratory rate, sleep HRV, wrist temperature, blood oxygen and disruptions against your usual range.
Deep plus REM sleep per night, with findings from your own best nights.
Daily scores, live heart rate, quick logging and complications on Apple Watch, arranged from your iPhone.
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FitRest reads the data already in Apple Health, so there is nothing to set up beyond granting access.
iPhone, iPad and Apple Watch. Requires iOS 17 or later.