Here's what we know about Bobby Murphy, Snapchat's mysterious billionaire cofounder

CEO Evan Spiegel is the public face of Snapchat parent company Snap Inc., but Bobby Murphy also wields considerable power as its cofounder and chief technology officer.

Together, Murphy and Spiegel own the vast majority of Snap's voting stock, giving them complete control over the company's future. Now that Snap has gone public, Murphy has an estimated net worth of around $5.4 billion.

Unlike Spiegel, Murphy has maintained a decidedly low profile since the beginning of the company. He's only given a handful of interviews, and little is known about his personal life.

People who've worked with Murphy describe the 28-year-old as smart, friendly, and quiet.

"I'd describe him almost like a monk," Snapchat's first hire, David Kravitz, told Forbes in 2014. "I don't think I've ever seen him upset."

We've pulled the highlights of Murphy's life and career from interviews he's given over the years and Business Insider's own reporting: