Mightybell - Build a community and a business on mobile
Discourse - Discourse is an open source discussion platform built for the next decade of the Internet.
MyTalk - Build a community around your product
Confluence - Confluence is content collaboration software that changes how modern teams work
Hey.Cafe - Hey.Café is a social network built around communities called cafés.
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.