I’vE notice an huge battery drain after updating my ultra 1 to watch os 10.1
Yesterday at 00.30 am I had about 65%, this morning at 6 am the watch was off with no battery remaining (only used for sleep tracking with default sleep app)
Charged for 30min and was at 50% now after 5 hours is at 24%
For anyone still suffering from extreme battery drain I’ve run across this thread on an Apple.com discussion board which solves the problem.
tldr: Removing the MobyFace app seems to have solved the issue for many, as it has for me.
Hope this helps!