It appears that the billion-user club is about to get a new member.
Facebook announced the acquisition of messaging app WhatsApp on Wednesday, a deal worth up to $19 billion in cash and stock that puts serious muscle behind Facebook's international reach.
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In a call with investors to outline the acquisition, Facebook CEO Mark Zuckerberg and WhatsApp CEO Jan Koum hinted multiple times that they expect WhatsApp to become a billion-user platform, a milestone that Facebook eclipsed less than 18 months ago.
"WhatsApp is the only widely used app we've ever seen that has more engagement and a higher percent of people using it daily than Facebook itself," Zuckerberg said on the acquisition call Wednesday, noting that WhatsApp has doubled in size over the past year. "Based on our experience of building global services with strong growth and engagement, we believe WhatsApp is on a path to reach over one billion people in the next few years."
WhatsApp has already over 450 million monthly active users (320 of which are daily active users), and the company claims it is adding more than one million new users per day. For comparison purposes, Twitter added nine million new users in the entire Q4 2013; Facebook did better, adding 40 million in the same three month period, but growth is slower for a company with a billion-plus users already under its belt.
Facebook reached one billion in October 2012, roughly eight and a half years after launch. Could WhatsApp hit one billion even faster?
Assuming the company continues to add one million users per day, then yes. Much faster, actually.
WhatsApp is on pace to reach one billion users in August of 2015, approximately a year and a half after being acquired by Facebook. At that time, WhatsApp will be a little more than 6 years old, achieving the billion user milestone more than two years faster than Facebook did.
Of course, WhatsApp's trajectory is likely to change over time. Just like other consumer services like Facebook and Twitter, growth may slow as the user base gets larger and new users are harder to find.
Regardless of the timing, Zuckerberg seems poised to own two separate billion-user brands in the near future, and he's understandably excited.
"Services in the world that have a billion people using them are incredibly valuable," he said.
For $19 billion, we'd certainly hope so.

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