Left phone charging to 100% overnight. I woke up and checked email on phone. Noticed battery had already went to 98% after just looking at email. I turned phone off and back on the battery % then said 89%. Turned the phone off again and it dropped another 2%. Kept doing this, and kept going down 2% each time. Got to work and plugged in to charge & it went back up to 94% quickly. Wonder if it's a software bug after update to cyan/8.1 or battery becoming defective?