April 30 (UPI) -- Jan Koum, the CEO and co-founder of WhatsApp, announced Monday he is leaving the company, which is owned by Facebook.
Koum leaves the company more than nine years after he and Brian Acton created the messaging app. Facebook bought the company in 2014 for $19 billion.
He said he was leaving to pursue interests such as working on his car, playing ultimate frisbee and collecting Porsches.
"I'm leaving at a time when people are using WhatsApp in more ways than I could have imagined. The team is stronger than ever and it'll continue to do amazing things," Koum said in a Facebook post announcing his resignation.
"And I'll still be cheering WhatsApp on -- just from the outside."
The Washington Post reported that Koum's departure comes after he clashed with Facebook over its use of personal data and privacy issues.
Facebook CEO Mark Zuckerberg said he would miss working closely with Koum.
"I'm grateful for everything you've done to help connect the world, and for everything you've taught me, including about encryption and its ability to take power from centralized systems and put it back in people's hands," he said in reply to Koum's Facebook post. "Those values will always be at the heart of WhatsApp."