Facebook recently updated the iOS app to version 5.5, which included the same free calling feature its Messenger app has had for a while now. As with the Messenger version, you're able to place or receive a call over both a Wi-Fi or 3G/LTE connection from your iPhone.
The option to place or receive a call is available only on the iPhone, not on the iPad or Web site.
As you can see in the video above, placing a call is simple:Launch the Facebook app and view your Messenger contact list. Open a conversation with a … Read more