I posted it over in the vivoactive forum, didn't know this one was here. I'd like to have a custom data field that estimated remaining battery time, if that is even possible. IE, get battery level at start, then use activity time and the change in battery level to estimate remaining battery life, maybe updated every two minutes or so.
It seems like it should be simple enough, but that doesn;t mean it is. (My vivoactive currently drains about 15%/hr, Garmin claims it should be closer to 10.)