Slack is proving that the battle for chat app supremacy is far from settled.
Despite chat's basic functionality and its long history as part of the web (remember AIM?), Slack is making significant inroads in the workplace, where its platform is now used by 1.1 million people every day.
According to a new batch of data released by Slack today, over 300,000 people use the premium, paid version of its software — a base that has helped it build $25 million dollars in annual recurring revenue.
Slack also announced it has hired April Underwood, Twitter's former Director of Product, as its Head of Platform.
"Slack will become an even more powerful product as the platform evolves. We'll be making it easier for established enterprise applications and app developers to grow their businesses." said Underwood in a release.
Founded sixteen months ago, Slack has raised $340 million from Accel, Andreessen Horowitz, Google Ventures and more.