I have a series zero Apple Watch from the day it was released and still wear it now. I have figured out how to use it to track my sleep: charge Apple Watch les

I have a series zero Apple Watch from the day it was released and still wear it now. I have figured out how to use it to track my sleep: charge Apple Watch less. I charge Apple Watch twice a day, once in the morning, once at night, for about 15min each time. My Apple Watch has enough energy for me to use all day and track my sleep using the Sleep++ app. https://itunes.apple.com/us/app/sleep/id1038440371?mt=8 https://itunes.apple.com/us/app/sleep/id1038440371?mt=8 I _sometimes_ have to charge it at work, but in general, this charging method has worked for me.