https://www.theverge.com/tldr/2019/2/4/18210980/slack-ipo-messaging-apps-competition-chat

Slack was late to the world of workplace messaging apps. When it arrived in in 2013, it didn’t appear to offer much that was new — chat rooms and direct messaging were already available in a host of apps. But its co-founder Stewart Butterfield cannily presented it as a powerful alternative to email and, over time, as a command hub for the workplace that would integrate all the other software a company uses into a single interface. Slack spread like wildfire, and today is worth at least $7 billion, The Wall Street Journal reported.

Now the company plans to make its stock available for purchase: the company filed its initial public offering today. It is expected to become one of the most valuable tech companies to go public since Snapchat.