The creators of instant messaging service WhatsApp can now comfortably call themselves billionaires after signing a $19 billion deal with Facebook. But the duo's road to becoming billionaires several times over has been filled with humble beginnings and setbacks Koum, 37, who co-founded the app with Brian Acton in 2009 co-founded WhatsApp in 2009, and five years later, is now estimated to now be worth about $6.8 billion. But at one point he was a teenage immigrant who lived on food stamps. The 'long time'-friend of Facebook CEO Mark Zuckerberg was just 16 when he moved to the U.S. from Ukraine.
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Jan Koum, 37, moved to California from the Ukraine when he was 16
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Founded mobile chat-app WhatsApp with Brian Acton in 2009
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Koum has known Mark Zuckerberg 'for a long time', Facebook CEO said
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Acton was rejected by Facebook and Twitter in 2009
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Koum signed $19bn deal at welfare center where he used to collect handouts
WhatsApp founders Brian Acton, left, and Jan Koum at their company headquarters in @placeholder, California