Light-sleep timing, a fade-in alarm, and a silent wrist-tap wake-up.
Since the app is already listening to your night, it might as well end it well. The built-in wake-up alarm stops the recording when it rings. Smart Wake can pull the ring time earlier, to a moment when you're sleeping lightly. And an Apple Watch can do the whole job silently with wrist taps. This page covers all three, plus the backstop behind them.
Set a wake-up time in Settings under Wake Up, pick an alarm sound, and the recording ends with the alarm. One action stops the sound, the taps, and the night's recording all at once.
The alarm fades in. It starts at a clearly audible level and ramps up to full volume over the first few seconds. If you change the alarm settings mid-night, they apply to the running recording right away. No restart needed.
Getting yanked out of deep sleep is what makes some mornings feel like surfacing from the bottom of a pool. Smart Wake gives the alarm a window instead of a deadline. Choose 15, 30, or 45 minutes, and inside that window before your set time, the app looks for a moment when you're sleeping lightly and rings then.
It decides using the same live sleep staging behind Sleep Insights, plus the most reliable leading signal there is, which is your own movement and sounds. Stirring or murmuring inside the window can set the alarm off right away, since you're already surfacing. A light-sleep reading on its own is treated more cautiously and only fires in the later part of the window, so the alarm can't keep costing you half your window every night. A confident deep-sleep reading holds it back.
If no good moment comes along, you lose nothing. The alarm rings at your set time like a normal alarm would. When Smart Wake does fire early, the wake-up notification and the next morning's summary both tell you.
Smart Wake needs Sleep Insights turned on, because without the stage engine there's nothing to time the wake against. Settings warns you in both places if one is on without the other. While it's armed, the lock screen's Live Activity shows the alarm with its window, for example "6:30 – 7:00 AM".
With an Apple Watch on your wrist, the alarm can reach you as taps instead of sound, so you wake up and your partner doesn't. Turn on Wrist nudge on Apple Watch in the Wake Up settings and at alarm time you get a steady rhythm of taps, a few seconds apart, in two waves over about six minutes, so a deep sleeper gets a second chance.
You can run the taps alongside the alarm sound as backup, or on their own as a fully silent alarm. Dismissing the notification on the watch stops everything, sound, taps, and recording, and just unlocking your iPhone counts as awake and cancels the rest. A Test button in Settings lets you feel the tap pattern. Lock the phone after tapping it, since iOS only mirrors notifications to the watch while the phone is locked.
This works with the watch app closed and the phone locked, and the option only shows up when a watch is paired. Setting the watch's haptics to Prominent, in the Watch app on your iPhone, makes the taps a lot firmer.
A fair worry about an alarm inside a recording app is what happens if the recording dies overnight. So there's a backstop. When you arm the alarm, the app also schedules an independent system alarm slightly after your wake time, through iOS's alarm framework on recent versions and a time-sensitive notification on older ones. If the app fires your alarm normally, the backstop gets cancelled before you ever see it. If something silenced the app overnight, the backstop still gets you up.
In silent wrist-tap mode the backstop stays silent too. You get a tap instead of a blast, so the whole point of not waking your partner holds up even when something goes wrong.
