Public - Group chats.
ClickMeeting - Collaborate with partners and clients using ClickMeeting professional web conferencing software. Try it now, FREE!
nocnoc - Instant group chat invite via link
Zoom - Equip your team with tools designed to collaborate, connect, and engage with teammates and customers, no matter where you’re located, all in one platform.
Viber Communities - Group chat with up to 1B members, admin controls and more
BigBlueButton - Engage Your Online Students. BigBlueButton is a web conferencing system designed for online learning.