Facebook Social networking company says that the function of Facebook video
call is to overthrow almost around the world.
Although most countries have access to it and perform good quality service,
Facebook is not set up in some countries, because they are trying to improve
the video quality in these areas. This is probably due to the velocity of the
mobile telephone networks in these countries.
Facebook has the goal to make video calls with a complete experience, even
if users are not using Wi-Fi. That is, in some countries, video telephony takes
a little optimization before disposal in total.
Either way, that's a big step for Facebook because it Messenger program was
introduced only in 18 countries. If you have not downloaded the Messenger, but
it's available for free on Android and iOS.
source: Facebook