C calviin macrumors regular Original poster Oct 31, 2011 #1 Looking at my iPhone, the compass calibration is always on and that's what's using a lot of power. Once I turned it off, voila, battery lasted all day easily. Dunno if that applies to others but it's worth a try.
Looking at my iPhone, the compass calibration is always on and that's what's using a lot of power. Once I turned it off, voila, battery lasted all day easily. Dunno if that applies to others but it's worth a try.