Question: app to do video call?
Answer: Skype. Skype is one of the oldest and most famous apps for calls. ... 
Facebook Messenger. Facebook Messenger is another free app for iPhone, Android and Windows Phone to make video calls on the go. ... 
Google Hangouts. ... 
Apple Facetime. ... 
Line. ... 
Viber. ... 
Tango. ... 
KakaoTalk.