Two days ago I received an extended life battery from GorillaGadgets. While I'm not happy with the battery life so far I did discover a great benefit from the larger battery cover that came with the battery. The fingerprint swipe now works first time every time. The thicker case supplied with the battery actually moves your finger further away from the fingerprint sensor. In fact my finger doesn't actually contact the sensor now. I first thought that I would have to press extra hard when swiping to get my finger nearer the sensor. But, I discovered that a normal swipe unlocks the phone on the first try. With the original cover I would usually get one or two "swipe was too fast' messages before the phone unlocked. I haven't tried it but maybe with the original battery cover installed lightly swiping or even swiping but not actually touching the sensor might decrease unlock failures.