Just today Facebook has announced an add-on to its app on iOS devices–iPad and iPhone. It’s the Chat Heads which have been implemented earlier on Android through the Facebook Messenger app.
As the name implies, the Chat Heads show the head or face of your contacts, on a circle, who have just send you private messages. The number of unread messages is reflected on the Chat Head by the usual red-colored number. You can re-position the Chat Head by dragging it anywhere on the screen(3rd image) and remain on top of any screen you’re opening like composing or reading SMS (4th image).
The screen shots above are from an Android phone. Remember you have to install the Facebook Messenger app on your Android phone to use the Chat Heads. For iPad the Chat Heads is already available in the App Store while Chat Heads and Stickers for iPhone will start to roll out in few weeks.
Facebook also introduce the Stickers which allow us to put some smileys along with our messages.