WhatsApp co-founder Brian Acton announced his departure from the company Tuesday, three years after Facebook Inc. bought the messaging app for $22 billion. "After 8 years at WhatsApp, I have decided to move on and start a new chapter in my life," he said in a Facebook post. Acton said he intends to start a foundation "focused at the intersection of nonprofit, technology and communications." Acton ran WhatsApp's engineering team. His fellow co-founder, CEO Jan Koum, will remain at the company. Last week, Facebook said it would eventually start charging companies for some of WhatsApp's features as it seeks a path to monetization. In July, Facebook said WhatsApp had reached 1 billion daily active users, but that it will take a few years to start making money from the app. Facebook FB, -0.32% shares are up 17% in the past three months, and up 50% year to date, compared to compared to the S&P 500's SPX, +0.34% gains of 3% and 12%, respectively.