Hi gays I have use it for 2-3 hours its experiance was really awesome it gives me less features compared to fb messanger skype imo etc. The mai thing which I really like is its knock knock feature
And the best part is that you really feel is that it can c onnect with the speed of 8000 kpps to means less than 1mbps so when you are use 3g or higher net speed then you get a really amazing experiance
It has cool and easy start which is you just have to link it with your email.
Then autimtically it reads your contact means who are using duo are not .
Its second feature is you can see your favourate contact on the bottom of the screen with a bold letters
So how to use it
If yiu are a new user you search in your contact and calls to your friend or whome you you want to call
For reciveing it also very easy
When calls come from any one you see his face or his camers display you jyst have to swife upward
For rejection of the calls
You just have to swipe down
Now I thinks you really knoa about google duo ( best video calling app)