Slack doubles in size in four months to 1.1 million daily active users

Slack doubles in size in four months to 1.1 million daily active users

Slack, the much buzzed about team communications service that’s shaking up business communications, has announced that it’s passed one million active users per day.

The news comes just four months after the company shared that it had passed 500,000 daily active users.

The growth is fast, but not unprecedented: over the same time period in 2010, Yammer saw similar growth hitting the 1 million mark within 18 months of launching. Those figures, however, were overall user signups and not how active its user base was.

Since February, Slack has also grown its paid customers to 300,000, up from 135,000. The company opened up to the world for the first time in August 2013.

Much of Slack’s growth could be attributed to communities and groups taking advantage of Slack’s free plan to chat as a group despite the company’s lack of support for such setups.

Slack has also announced that it’s hired April Underwood, formerly of Twitter and Google, as Head of Platform to oversee its partnership, API integrations and developer relations.

Slack plans to invest over the next year in surfacing third-party services in the product, along with adding new functionality.

Business messaging is a crowded space, with other services such as Atlassian’s HipChat, Flowdock and Chatgrape offering similar functionality to Slack.

It’s likely that Slack will introduce audio and video calling over the next year, which will help it stand out from its competitors.

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