Jelly Bean has debuted a new feature great for any user: safe mode. When you reboot into safe mode, it disables all 3rd party apps. So if your phone is acting up, crashing, draining battery fast, or anything, entering safe mode can definitely prove if it’s an app issue or something more serious. It might also be a good battery saving mode, but that’s not what it’s made for.
To enter it, hold the power button and wait for the power menu to show up. When it does, long press “Power Off” and you’ll get a safe mode prompt like in the screenshot. Easy, huh? Thanks, Android devs, for such a nice feature in a stock build of Android!