Facebook's stock rose more than 15% in afterhours trading on Wednesday after the company reported that 41% of its advertising revenues now come from mobile.
The surprising mobile numbers -- Wall Street had been expecting Facebook to report the figure at 33% -- contributed to revenues of $1.8 billion for the quarter, which was more than the projected $1.62 billion. Earnings per share came in at $0.19, which surpassed the $0.14 that analysts had been expecting.
The company also reported that it now has 819 million monthly mobile users, a 51% jump over the same period in 2012. Overall, Facebook has 1.15 billion monthly active users and 699 million daily active users.
Facebook launched its ad business a year ago; the 41% figure was built up within the last 12 months. Advertising represents 88% of Facebook's total revenues.
"We've made good progress growing our community, deepening engagement and delivering strong financial results, especially on mobile," said Mark Zuckerberg, Facebook founder and CEO, said in a statement. "The work we've done to make mobile the best Facebook experience is showing good results and provides us with a solid foundation for the future."