Imo is best app for video calling and to chat, which consumes very less data while video calling and during chat. That is very good thing and plus point of this. I mostly use this app. Its layout and design. After opening this app two options are given as chat and contact if we click on chat then it will open the chat function and chat pattern, other side clicking on contact it will show the all contacts numbers at which we want to chat or video calling.
One thing I deeply relized that while video calling it gives the picture qualty good and clear no stoping and poor network I have to face. Very usefull app.