Facebook Messenger hits 600M monthly active users

Facebook, Messenger and Instagram apps displayed on a smartphone
Adam Jeffery | CNBC
Facebook, Messenger and Instagram apps displayed on a smartphone

Facebook Messenger has amassed more than 600 million monthly active users, CNBC has learned, as CEO Mark Zuckerberg seeks to establish his company's dominance in the newest mobile battleground.

It's an eye-popping growth number, considering it's been just four months since Facebook announced that Messenger had crossed the 500 million user mark. And as Zuckerberg prepares to take the stage at the company's F8 Developer Conference, it's a ringing validation of the company's controversial strategy to remove Messenger from the main Facebook mobile experience and all but force users to adopt something new.

Splitting off Messenger as a separate app caused headaches at first, as users rebelled against the move. But it was essential to jump-starting the latest wave of usage, Facebook growth VP Javier Olivan told CNBC earlier this month. Direct communication features were getting lost in the interface of the main Facebook app, especially as users migrated from PCs to smartphone screens.

The growth of Facebook's home-grown Messenger is especially significant because it defies the popular narrative that Facebook has had to buy growth as its core social networking experience ages. Yes, Zuckerberg was prescient enough to snap up Instagram for about $1 billion just before the company's IPO and WhatsApp for more than $19 billion a year ago. But Facebook's own Messenger is apparently seeing growth rates on par with those: Instagram boasted of 300 million monthly active users at the end of last year, and WhatsApp logged 700 million at around the same time.

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All of that amounts to an embarrassment of growth riches at a time when pundits like to talk of a maturing landscape in social media and mobile. And it puts some pressure on Zuckerberg to explain how Facebook plans to differentiate between the products—and of course turn them into money-makers along the way.

Zuckerberg's plans for Messenger should take up a healthy chunk of his opening keynote at F8, scheduled for 1 p.m. EDT. He's expected to show how outside developers can build pieces of Facebook's messaging experience into their apps.

Despite Facebook's scale, it won't be an easy sell: The company has yet to establish a track record of supporting companies who want to develop businesses on top of its platforms. The web-browser-based Facebook Platform that fueled the meteoric rise of gaming companies like Zynga proved to be less than stable, as Facebook changed the way developers could engage users. Similar challenges hit fledgling social video and news efforts.

Facebook does seem to be putting its money where its mouth is when it comes to expanding the horizons of fast-growing Messenger. The company last week announced that it is enabling long-rumored person-to-person debit card payments in Messenger.

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