But none of them work well across platforms. If you've got an Android phone and your friend has an iPhone it just wasn't a great experience to try and video chat.
The interface for Duo is very intuitive and easy to use. Like most video chat apps you just choose who you want to talk to and they get notified of your request to chat.
Where Duo is unique is with their "Knock knock" setting. Instead of just displaying the caller's profile picture when they call, knock knock lets you see video from your caller's device before you accept the call.
This could be helpful in determining if a call is urgent, or if you can get back to the caller at a more convenient time. (eg: They could hold up a note saying "This is urgent!", or some other visible indicator you recognize. Knock knock is enabled by default but can be turned off.
Duo offers high quality video chat over WiFi or using your phone's mobile data. Google indicates Duo will seamlessly switch between cellular and WiFi, meaning your calls won't drop as you move from one to the other.
For those concerned about security, Google says the calls are end-to-end encrypted, which should prevent anyone from listening in on your conversation.
With decent video Duo could be a great way to stay in touch with friends and family who use different devices while on the go.
The Duo app is free, you can get it at Google Play or in the Apple app store. Given the price why not try it out with some friends and see if you like it?
-The Home Geek.