> I can't speak for the other applications, but have you used Hipchat? It's really poor in comparison to Slack.
You're splitting hairs. They are both chat apps for crying out loud.
Slack grew as fast as it did because it got pimped to us by VCs and thought leaders and then wannabe thought leaders and down all the way to the bottom rung of the societal ladder. Great strategy by Slack but there is nothing special about it (the product).