Allows publishers to create articles that load natively inside Facebook’s iPhone app (it’s iPhone-only for now), rather than sending users off to the Web.
Facebook gets to keep users in its app, seeing articles that load instantly, rather than going off to a website that they may stay on instead of coming back to the warm, blue arms of its own domain.
Read more here: http://thenextweb.com/facebook/2015/05/13/facebook-launches-instant-articles-for-iphone-native-content-from-buzzfeed-the-bbc-and-more/