updated 04:50 pm EDT, Tue August 9, 2011
Takes unusual single-purpose approach
Facebook has released a secondary iPhone app, Facebook Messenger. Unlike the company's primary app, Messenger is single-purpose, devoted to entirely to direct communication with other Facebook users. Messages can be sent to individuals or groups, and optionally include photos.
Location services can be used to find a person's own position and that of friends. Like most iOS messaging tools, Facebook's can also provide notifications of incoming talk. The app is a free download for any handheld running iOS 4 or later, although there is no native iPad interface to speak of.