a role for your front-facing camera which previously had been bored whenever you were using the Facebook app. Now, you can show the world who you really are by snapping self-portraits with the shooter in front. While in camera view, you will see a button in the top/bottom on the left hand side which will allow you to grace others with your smiling (or unsmiling, the choice is yours) face.
The update also brings some new messaging capabilities including the ability to switch between conversations, include friends of friends, share bigger photos, and see who’s available online. Facebook also tossed in at no extra charge (relax, its still all free) some security updates, bug fixes and the usual stuff that you can't see.
The update should be waiting for you at the Google Play Store.
source: Facebook via GSMArena