To turn the device on, press and hold the Power/Lock key until the device vibrates. Note: If you are unable to turn your phone on, plug the phone into a power source for 15 minutes, then try again.
To turn the device off, press and hold the Power/Lock key until the power menu options appear.
Tap Poweroff.
Tap OK.
If you are unable to power your device off or if it becomes unresponsive, press and hold the Power/Lockbutton for 10 seconds.