Yep, Duo is pretty good for video, but not many people know about it, and it has no group video call for the web. I would guess most of iFolks use Facetime. Business use is a whole different ball game, Zoom is the rising star there, most of my business calls are on it. Internally we also use Slack for video calls. Although Slack is technically and feature-wise rather poor when it comes to video, we use it extensively for quick written communication, so it's easy to hop on.