[Ed Zachary]

You see, that's just the thing.
We did absolutely nothing to the Boss Lady's phone and it is getting great battery performance out of the box, from day one.
We did the same with mine and it can't stay alive more than 3 1/2 hours, doing NOTHING, before it starts crying for the charger.

The "old" one, that came the same day as the Boss Lady's, was that way for five days. And it was constantly HOT. Unless I completely powered it down.
The new one doesn't get hot. But it is still jonesing for the charger.

I let the update finish, so now the firmware version is up to date.

Taking the SD card out seems to have had no effect, either.