The rezound fast boot option is check by default. This option does not play nice with some apps, causing the device to boot loop. The only way to fix is to do a hard reset, thus loosing all your setting and restoring to factory condition. Hard Reset: Pull Bat Reinstall Bat Press and hold volume down and then press and hold power until boot loader comes up and then release. Highlight reset and then press the power button to select. Once device resets, make sure you go into your setting and turn off the fast book option. Problem solved!