Here are the messaging apps Slack crushed on its road to IPO

1:35pm PST - February 4th, 2019    so far gone - The Verge

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 present…