Google Duo is one of the best video calling apps for Android with a simple interface. It is quite easy to log in and verify your number, and you can make fast video calls just like making a standard phone call.
Its unique “Knock Knock” feature lets you have a live preview of the caller before you receive the call. One can also leave video messages to the other person if he/she is not available at the moment.
Google Duo is one of the most popular apps and is available on Android and iOS.