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My watch used to get me through an entire day (16+ hours) and still have plenty of juice.

Since upgrading to OS 2, it's dead by 7hours or so.

I deactivated data usage sending to Apple, turned off most the app notifications and uninstalled most of my 3rd party apps... and still not much help.

I wish Apple would add an app battery usage tracker like they did for iOS to see what's taking up all the power!
 
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