How to Make Free Calls Using Facebook Messenger App

Here the good news for Facebook Messenger users the company now rolled out a new feature for iPhone users from US, that allows you to make a free calls to your Facebook friends.

To make free calls tap the "i" icon from top right corner of the chat, then select your Facebook friend and then hit Free call button. Your friends also have to installed Facebook Messenger app on their iPhone to receive your voice calls.

This free call feature available in US only, there is no official word for other countries.

Source - mashable