Facebook posted their end of year financial results this year, beating Wall Street expectations, showing growth in mobile revenue.

The social networking site impressed investors with the results, recording revenues of US$1.59 billion for the fourth quarter, representing a rise from $1.53 the previous year.

As investors took profit on the back of the release, shares fell as much as 6% during after hours trading.

"In 2012, we connected over a billion people and became a mobile company," said Mark Zuckerberg, Facebook founder and CEO.

"We enter 2013 with good momentum and will continue to invest to achieve our mission and become a stronger, more valuable company."

Positives for the company includes the 23% of advertising revenue coming from their mobile division, reaching $1.33 billion.

In a first for the social media giant, mobile members beat online users, with stock rising over 30% during the past three months.

For 2012 as a whole, Facebook recorded $5.089 billion growth, beating that of 2011 ($3.7 billion), ending the year with $9.6 billion cash in the bank.

Net income during Q4 stood at $64 million, compared to $302 million for the same period last year.

Cause for optimism?

Industry experts were quick to comment on the results, with Ovum's principal analyst Eden Zoller suggesting the company has turned a corner during the year.

"Facebook Q4 2012 results give cause for optimism and suggest the company is on the right track following its disappointing IPO and the lacklustre two quarters that immediately followed.

"What stands out from Facebook’s Q4 results is the centrality of mobile for its service strategy and growth.

"Revenues from mobile advertising accounted for 23 percent of total advertising revenues compared to 14 percent in the previous quarter, with sponsored stories in the mobile news feed and app install ads proving effective.

"Wal-Mart alone delivered 50 million mobile ads to customers.

"This solid progress on the mobile advertising front should be applauded as a key challenge for Facebook has been how to monetize its growing mobile user base, particularly as an increasing number interact with the platform by only via mobile devices.

"Facebook reported 680 mobile monthly active users in Q4, of which 157 million were exclusively mobile."

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