How to Log Out of the Lite Version of Facebookby Ken Burnside
Facebook's "Lite" version was discontinued in 2010, but many aspects of it were folded in to the Facebook Mobile App, with versions available on both iOS and Android. Sometimes it's not appropriate to get notifications from Facebook on your phone. Due to the constraints of the small screen, the controls for logging out of the App aren't obvious.
Tap the "three bars" icon at the top left of the App. This pulls up the user controls on the Facebook App.
Scroll to the bottom of the page. Depending on the size of the screen of your mobile device, you may not see the log out option until you scroll down to the second screen of information.
Tap "Log Out." You'll log out of Facebook.