Cyberspace chat is a great way of connecting people with similar interests.
It comes with its own etiquette, or "netiquette", which may confuse or even intimidate a novice.
By the time I'm ready to take the call, I've missed it by a long shot.
In that way, video calling feels old-school before it's ever even cool.
Even if everyone decides to get down with video calling, Google needs to get tons of people to download the app if it is to become part of the world's messaging lexicon.
If the person in your phone book, the Knock Knock feature provides live video before you pick up. Turn it back on and video should return, too— though it doesn't always cooperate.
(the Duo ad does a great job showing you all the cool things you can do with Knock Knock, but mostly I use it to make sure everyone's clothed.) Swipe up to answer, and you're on the call. You can use Duo to call anyone, but it seems designed largely for calling the same people over and over.