Facebook's profit slipped to $64 million in the fourth quarter of 2012, beating expectations from analysts. A year earlier, before Facebook was publicly traded, it earned $302 million.

Revenue at the social networking site rose to $1.59 billion, an increase of 40% from a year earlier as advertising revenue continues to grow.

Facebook also said more of its daily users – over 600 million – are accessing the site via mobile devices than through the web, a first for the company. It also says it had 1.06 billion monthly active users in December - a new record for the site.