i think a day without apps first would be best, at least it would tell us if it is an app or not. one time on my gnex, i started getting random reboots when there were none before. about 3 days worth of reboots had me confused. i was about to flash the factory img, but i remembered i installed an app the day before the reboots started. even though i only opened it one time since i installed it, i decided to try removing it first. so i removed it, and never had a random reboot on my gnex since.