فیس بک سے مفت بین الاقوامی کال ملائیں-ایک حیرت انگیز اور آسان طریقہ 
Facebook messenger app also uses the VoIP, but using this you can 
make calls to US, UK and Canada citizens only. Using this service the 
calls are free but you need a good 3G/4G connection, but having Wi-Fi is
 recommended as calling needs a good amount of Data and speed, and your 
messenger app version should be 4.0+. The best part of using Facebook 
VoIP calling facility is that it’s not Mandatory to 
have Facebook messenger app for receiver to attend your call.
So 
here is the Step by Step process How you can make free call using 
Facebook messenger app. Here I am using iPhone but you can do it same 
for your Android device. But make sure that whom your are calling has 
added his phone number to its profile.
Free international calls using Facebook Messenger app on Android and iPhone
- Download and Install the Facebook messenger app on your Android or iPhone from there store and Launch the messenger app on your device.
- You must have a recent conservation going with the person whom you are calling. Just tap on the Conservation to open it and if you don’t have any recent conservation tap on the compose message button placed at the bottom right and here you can add the person’s name whom you want to call.
- Type anything in the message and send it, to start the conservation.
- Now just tap once on Contact info button, placed at top right corner like image below . Now you will able to see the contact information whom you want to call.
-   
- Here with Options like Timeline and others, you will see a Free Call button placed at the mid of the screen. As shown in the below image.
- Just Hit the Free Call button and you are done. You will be making free call to your desired contact.
That’s
 it, now you will be able to talk to your friends or relative for free 
of cost just using an internet connection. International calling rates 
are very high for US, UK and Canada, so for calling in those countries 
you can use this Facebook calling feature for absolutely no cost.But you
 have to keep the Push Notification On so it should alert your when 
someone is calling you.
