Why has Slack won when other group messaging plays lost? By keeping it simple. Thanks to Slack’s sensible chat room design, everything seems one click away. Private channels, easy integration, and effortless file sharing haven’t hurt, either.
The ongoing triumph, however, is behind the scenes. Throughout Slack’s three-year growth from zero to 5 million daily active users, Slack has managed to keep its service reliable and responsive—and has been commendably transparent about the outages and incidents that do occur. Slack has also attracted more than 100,000 external developers who have built 900 third-party apps at last count.