I’ve used AutoSleep for years - works great.

You can tweak it to most accurately record the time you’re in bed and how much is awake, light sleep, moderate sleep, deep sleep. It will automatically record a nap if I happen to take one during the day.

I usually charge my watch in the morning while having coffee and showering. It is on my wrist at all other times.

I’ve used Apple watches for several years to monitor sleep (now have a series 9).

Monitor heart rate, sleep quality, SP02, respiration etc.

It does tend to temper alcohol use - just a couple glasses of red wine result in zero deep sleep and increased heart rate throughout the night.

SP02 and respiration were indicative of a lung disease which I’m being treated for.