But now Zuckerberg is more excited about messaging services than photos. That's because he feels there's a cap on how many photos people want to share with each other, but they always want to be communicating in some form.
"I'm so excited about messaging," $4 Wednesday. "There are only so many photos you're going to want to share with friends - there's just a lot more people want to express."
Facebook is also letting up on mission to give people identities online. On the call, he was bullish on anonymous-friendly features.
"Things like anonymous login unlock different behaviors," he said. He explained that people are often more willing to share things and experiences when there isn't a name tied to it.
Facebook's job, Zuckerberg said, is to give people the tools they need to socialize and communicate- even if that means they don't match Facebook's founding principals.