Facebook is now giving its users a new advantage, It has now added a new features to it's Messenger for android and ios. We can now call to people free of cost but like as other messaging app it also need data connection.
Once you finally get to the Free Call button, Facebook will dial up your friend over Wi-Fi or your phone's data connection.
This feature is also added to Facebook home. This addition feature "Free Call" button ca be accessed from Facebook buddy's contact page.This feature is also available in 24 other countries including united state.