I already use an app and it seems actually incredible accurate for example I wake up at least once every night and also wake up half an hour before my alarm automatically and I can see it in the report the next day. Also when I fall back asleep, but not deeply, it shows.
HOWEVER at the end of the day it’s just a report of something I can’t really influence anyway. If I wake up I wake up, it’s not like my watch can force me to stay longer in the REM phase
To say that you can’t change your sleep patterns is like saying you can’t change your health by varying your diet.
Of course you can change your sleep patterns. It begins with understanding what they are via tracking, and then associating those patterns with other events: stress, diet, timing, alcohol. Because you aren’t conscious during sleep just means you have to be more deliberate. But it’s surprisingly easy — and beneficial — to try to optimize.i really hope a native solution for Apple Watch is on the way.