WhatsApp has hit a new milestone, having hit the 900 million monthly user mark.
Company founder Jan Koum announced the news on Twitter late last week.
The new figure means that that the Facebook-owned messaging app has grown 50 percent since this time last year, and has gained 100 million users since April. That will be music to Mark Zuckerberg's ears, as his company spent an eye-watering $22 billion (£14.2bn) on acquiring WhatsApp back in 2014.
Compared to other popular mobile communication services, WhatsApp is in fine form indeed. Both Twitter and Instagram have 300 million users, while Facebook's own Messenger service has 700 million.
Of course, the whole monthly active user metric has been questioned in the past. As Fortune points out, a person who only uses WhatsApp for a few minutes each month would count as a monthly active user just the same as someone who uses it regularly on a daily basis.
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There's also the small matter of monetisation. WhatsApp might be the messaging service of choice, but it still doesn't rake in a whole lot of cash for its Facebook masters.
Back in May, it emerged that Facebook was considering allowing businesses to use WhatsApp to directly message customers.
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