Originally Posted by **********

Reboot it first then upgrade to the latest iOS. Once it restarts double-click the big button to see what other programs are running at the same time. Kill the ones your don't need at the moment then try it again. If it still crashes connect it to your computer, run iTunes, and try rolling back to the previous or original iOS. (You won't lose your apps or data). If it still crashes after that call Apple to check your warranty status.