Quill

Quill is the best way to message with a team or group. Built for productivity and focus, Quill reduces notifications, collects conversations into threads, and gets out of your way — so you can get back to doing what you do best.

Voice Channels are just like regular channels — create as many as you like, add them to your sidebar, control access, and link to them. Scheduled video calls can be surprisingly formal. Capture the serendipity of an office, even when you're distributed.