Nice. Maybe with this I can convince my friends to move over to WhatsApp from Google Hangouts. The lack of desktop app support for Hangouts has been driving me nuts.
Hangouts does have a Chrome app (not extension, but app). Which runs in a pop-up mode and gives a user interface similar to android.
Also, it starts up with your operating system with a floating icon which stays at top of the windows if you want, and provides notifications. Your friends can use that if they want to stick to hangouts.
Because I can't cmd-tab to it. Because it brings every Chrome window to front if I just want to read a message. Because it floats on top of Chrome whenever it's open. Because I can't easily move it between monitors, or to a different part of the screen. It's also really rubbish at uploading files. Why can't I drag and drop? And how about search? You're Google ffs. Why do I have to go to Gmail to search Hangouts, instead of allowing search in, oh I don't know, how about in Hangouts?
Some of these may have changed since I abandoned Hangouts last year for Telegram, which still has the best desktop experience.
It's only the reason for it inasmuch as Hangouts is implemented in a way that behaves like this on Mac. It's not as if it's an inherent property of the OS.
Also, Hangouts would not need phone tethering