WhatsApp boss Jan Koum has left the messaging app over alleged clashes with parent company Facebook.
Koum wrote on Facebook that it was time to "move on" adding that he was planning on moving outside of technology for a bit.
"It's been almost a decade since Brian [Acton] and I started WhatsApp, and it's been an amazing journey with some of the best people. But it is time for me to move on," Koum wrote.
"The team is stronger than ever and it'll continue to do amazing things… And I'll still be cheering WhatsApp on – just from the outside."
Back in 2014, Facebook acquired WhatsApp for $19bn.
But a Washington Post report on Monday suggested that Koum had objected to Facebook's attempts to use WhatsApp's personal data and weaken its encryption.
Commenting on Koum's post, Facebook top-dog Mark Zuckerberg stated: "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.
"Those values will always be at the heart of WhatsApp."