If you like to use the dedicated Facebook Messenger application instead of the chat capabilities of the general Facebook app to keep in touch with friends, you’ll notice an update available in your iTunes/App Store.
The new version, numbered 1.5.2, not only fixes the “blue screen” startup crash for some together with other bugs but it will also start up considerably faster. Message scrolling is also faster so you can get quickly to a certain point in a conversation and the friend chooser now features Retina display photos. Follow the source link below to grab the app or just update via iTunes/App Store.
Source: iTunes App Store