Has anyone thought of using a watch to track their sleeping and then using another one for wearing during the day since the battery capacity doesn't really handle both? Maybe using their first gen for just sleep activity.
There are lots of people who use one Apple Watch to track their sleeping.
If you do you Google search, you should find a tutorial on how to do it. It involves wearing the watch at night and then putting it on the charger as you are getting ready for work/school.
Certainly, you ought to be able to do it with two watches, as well. My concern would be that the data would/might be separate (?) from each watch. But interesting idea.
No problem on the data being separated. You can pair two watches to one iPhone.
Switch between watches
Only one Apple Watch can be active at a time. To switch, take off your current watch, put on another one, then raise your wrist or move your arm. watchOS doesn't support wearing two watches at once, and it doesn't support sharing watches between multiple users at the same time.
Your watches share Activity and Workout information, so your progress automatically updates after you switch. If you put on a different watch to work out, you can still see all your steps, stand credit, and exercise credit for the day. Depending on how much information needs to sync, it might take a minute for you to see all your progress.
since the battery capacity doesn't really handle both?
It involves wearing the watch at night and then putting it on the charger as you are getting ready for work/school.
Not true. I charged my Watch once a day and Sleep++ worked fine all through the night. Some people will but more drain on a Watch during the day and it might not make it through the night but to say unilaterally that the capacity really doesn't handle both is incorrect.
This is what I did and generally the only time I charged it. If I had an unusually busy day, then I'd put it on the charger as prepared for bed. 10min on the charger was more than enough to get it through the night.
That said, I would never discourage anyone from owning two Watches for whatever reason.
If I put my watch in airplane mode while I sleep...
I thought I'd try that if my Watch ran out of juice during the night but it seldom got down to 40%. I don't like the battery to get too low as it uses up cycles quicker, and that usually means a shorter life for a battery.
I know I'm reviving an old thread but there is a new sleep app in the app store called SleepMatic and it works wonderfully well. it automatically detects sleep and also stores the info in the HealthKit plus has a terrific watch app. The developer is very responsive, I emailed him about an issue and received a reply within minutes and a fix was already awaiting approval by Apple. I would highly recommend this app.