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Days, then nights, then days again
Four on, three off, and the four are not the same four as last month. You are expected to be sharp for twelve hours whichever end of the clock the shift starts at.
In short
Your rota moves you from days to nights and back again, sometimes inside the same week, and there is no schedule to settle into because the schedule keeps changing. Every adjustment gets interrupted by the next one.
- missed night a week, bridged automatically
- 1missed night a week, bridged automaticallyA rota should not cost you a streak
- Live Activities, so the next alarm stays visible
- 8Live Activities, so the next alarm stays visible
- insight metrics, sleep debt among them
- 21insight metrics, sleep debt among them
There is nothing to adapt to
A body clock shifts by roughly an hour a day under the best conditions. A rota that flips you by eight or twelve hours every few days never gives it the run of days it would need, so you spend the whole month part-adjusted to a schedule that has already changed.
That is not a willpower failure and it is not something you are doing wrong. It is what happens to anyone on a rotating rota, including the colleagues who claim they are fine with it.
Anchor sleep is the one thing that reliably helps
The technique with the most behind it is an anchor: a block of four or so hours you sleep in on every kind of day, whatever the shift, with the rest of your sleep added around it.
Say your anchor is 04:00 to 08:00. On a night shift you sleep it after you finish. On a day shift you are in it before you start. On a day off you keep it and top up in the afternoon. The clock never gets a full reset, but it stops being dragged in a new direction every three days.
Setting one up without wrecking the first week
This takes a rota cycle to settle. It is worth doing on a run you already know.
- Look at a full cycle and find the four hours you could sleep on every kind of shift. There is usually one window that works, and it is rarely the one you would choose.
- Protect that block absolutely, including on days off. It is the only fixed point you get.
- Add the rest around it: a nap before a night shift, an extension in the morning after one.
- Blackout the room properly for daytime sleep, and wear sunglasses on the way home from a night.
- Give it a full cycle before you judge it. The first week of anything on a rota is unrepresentative.
If the rota is making you unsafe on the drive home, that is occupational health, not an app.
Using a sleep app when there is no pattern to learn
Some sleep apps assume a stable bedtime and get confused without one. Tock does not need a pattern. Every alarm is its own alarm, tracking follows whatever block you actually sleep in, and a sleep broken across a day off still counts as one night.
What to look at is the run, not the night. A single day after a night shift always looks bad. Sleep debt across four shifts, and whether your days off are actually clearing any of it, is the only question worth asking of the data.
The alarm has to be the one thing that never fails
Tock is built on AlarmKit, so alarms behave like system alarms: through silent, through a Focus, with the app closed, on the native full-screen alert. Given how much of your phone's life is spent muted, that is the part that matters most.
Live Activities and a Lock Screen accessory keep the next alarm visible without opening anything, which is worth more than it sounds halfway through a run when you genuinely cannot remember what you set.
The parts of Tock that apply to you
Not all of it will. These are the ones that do something specific about the problem above.
- Alarm on silentA phone that has been muted since the start of a twelve hour shift still rings. It is a system alarm rather than an app playing audio in the background.
- Sleep trackingThere is no schedule for it to learn and it does not need one. Each block is tracked on its own terms, days or nights, without assuming when your bedtime should be.
- Sleep scoreA rota cannot be judged one night at a time. Sleep debt across a full run of shifts, and whether the days off clear it, is the only reading that tells you anything.
- WidgetsLive Activities and a Lock Screen accessory so you can see the next alarm without opening anything, halfway through a run when the days have blurred.
- StreaksOne missed night a week is bridged automatically, which on a rota is the difference between a habit you keep and one you abandon in week two.
Where Tock will not help
- No app fixes circadian misalignment. A rotating rota keeps your body clock out of step with your schedule by design, and the best any app can do is help you sleep well inside a situation that is stacked against you.
- Smart wake needs a reasonably settled half hour before your alarm. After a night shift, in a bright room, it will often simply ring at your set time.
- Phone-only stage estimates degrade on short, broken daytime sleep. Read the totals and the stretches rather than the stage split.
- If you are microsleeping on the drive home or the fatigue is affecting your work, that is occupational health and a doctor, not a phone. Tock is not a medical device.
Tock estimates your sleep and is not a medical device. Nothing it shows you is a diagnosis, and anything that worries you is a conversation for a doctor rather than an app.
Questions people ask
How do I sleep when my shifts keep changing?
Anchor sleep is the technique with the most behind it: pick a block of about four hours you can sleep in on every kind of shift, protect it including on days off, and add the rest around it. It will not fix the misalignment, but it stops your clock being dragged somewhere new every few days.
Does Tock need a regular schedule to work?
No. It does not learn a bedtime and it does not assume one. Alarms are set per alarm, tracking follows whichever block you actually sleep in, and daytime sleep is treated the same as any other night.
Does sleeping during the day count as a night?
Yes. Tock counts the sleep you take, not the hours it happened in, and a block split across a day off is still counted as one night rather than two short ones.
Will my streak survive a rota?
Mostly. A night counts at 90% of your goal and one missed night a week is bridged automatically, which is designed for exactly this. A run of four nights where you barely slept will still break it, and honestly it should.
Other situations
The same problem seen from a different bed.
- Night shift workersYou finish at 7am and try to sleep while the sun is up, the neighbours are drilling and your phone is on silent so nothing wakes you. Then you have to get up on time anyway, in the middle of what your body still thinks is the afternoon.
- Light sleepersYou wake at everything, and then you are awake for forty minutes at 3am doing arithmetic on how much is left. By morning you cannot say what woke you, only that something did, several times.
- Travellers with jet lagYou landed, you are on local time on paper, and your body is running four or eight hours behind. Wide awake at 3am, unusable at 3pm, and it lasts roughly a day per time zone.
- People who hate morningsThe alarm goes off and you feel physically wrong. Not tired exactly, more like you were pulled out of something, and it takes the better part of an hour before you are a person again.
Elsewhere on the site
A different corner of the same problem.
- Wake timesWaking up at 8:30amBedtimes by sleep cycle for a 8:30am alarm.
- BedtimesGoing to bed at 10:00pmWhere to put the alarm after a 10:00pm lights-out.
- Sleep by ageHow much sleep preschoolers needThe American Academy of Sleep Medicine recommends that children aged 3 to 5 years sleep 10 to 13 hours per 24 hours, including naps, on a regular basis. This is the final band where daytime sleep counts toward the total; from age 6 the figures are given per night.
- NapsThe coffee napA coffee nap means drinking caffeine and then immediately napping for about 20 minutes. Caffeine takes roughly 20 to 30 minutes to have a noticeable effect, so it does not stop you falling asleep quickly, and you wake as it takes hold. The two effects add rather than cancel.
- Wake tonesSunrise alarmA sunrise alarm clock is a bedside lamp that brightens over roughly 20 to 30 minutes before your set time, and the light is the part you are paying for. Tock is an iPhone app with no light hardware at all, so it takes the timing half instead: a soft wake tone rung at a lighter moment inside the last 30 minutes rather than at a fixed time.
- Head to headAutoSleep vs PillowAutoSleep suits the person who wants every number and no recurring bill. Pillow suits the person who wants the night caught automatically and presented calmly, then written properly into Apple Health.
Start with the moment you get woken
It is the one part of your night you can change tonight. Tock waits for a lighter moment in the last half hour and rings a little early when it finds one.