Despite only launching in February, enterprise messaging app Slack has built up a dedicated following, and has just closed a funding round with $120m (£75m) of investment that places the companys value at $1.12bn.

The funding round, which was led by Google Ventures and Kleiner Perkins, marks Slack as one of the fastest growing software-as-a-service companies ever, with company figures suggesting that over 30,000 teams use the app, totaling 268,000 active users.

Slack is also notable in that its success comes largely from word-of-mouth advertising, with little money spent by the company on marketing its software to potential customers. It received a considerable boost in profile in early October when a security flaw revealed the internal team names of high-profile customers such as Apple, Google, Twitter and Microsoft. While Slack moved quickly to correct the error, the news that such large companies had adopted the app led to a boost in use.

Prominent investor in the company Marc Andreessen commented on the meteoric rise of the company on Twitter, stating, “I have never seen viral enterprise app takeoff like this before – all word of mouth.”