Facebook's group messaging app was launched just a little more than two months ago. Messaging using Facebook Messenger goes around mobile phone companies' text messaging service and is free. Messages can, however, be sent to people without a Facebook account using conventional mobile phone text message services. This week it received a significant upgrade to version 1.5. Facebook Messenger for iPhone and Android 1.5 gains presence features that lets you know who is on Facebook and who is mobile. [...]

Read More: Facebook Messenger Updated for Android & iPhone. BlackBerry Gets an App Too