While Apple's iPhone sales have stalled and Twitter's fortunes continue in a downward spiral, one company that continues to go from strength to strength is Facebook. The social media giant reported record fourth-quarter earnings yesterday which beat revenue and user growth estimates. The resulting 12 percent increase in stock value meant that CEO Mark Zuckerberg became the sixth richest person in the world.

Facebook generated $5.841 billion in revenue and earnings of 79 cents per share for the final quarter of 2015, beating forecasts of $5.36 billion and 68 cents per share. The report shows a rise of around 52 percent over the same period last year.

Average revenue per user, or ARPU, is also rising, up nearly 26 percent to $3.73. Facebook will be especially pleased with this increase, as it shows the company continues to make more money off the same size user base.

Facebook revealed a series of statistics for last year: On average, 1.04 billion people use Facebook every day, up 17 percent from the previous year, and 934 million people access the site every day on a mobile device, up 25 percent. It also said that it has 1.59 billion monthly active users (up 14 percent ), and 1.44 billion are monthly mobile users (up 21 percent ).

Facebook said that mobile ads accounted for 80% of total ad revenue in the quarter, compared with about 78% in the third quarter and 69% a year earlier. "Heading into 2016, it's clear that consumers have shifted to mobile, and businesses know they need to catch up," Sheryl Sandberg, Facebook's COO, said on a conference call with analysts.

The good news caused Facebook stock to rise 12 percent, bringing its total increase over the last 12 months to around 25 percent. This meant that Zuckerberg's net worth jumped by $4.85 billion to $46.2 billion, causing the CEO to surpass Oracle chairperson Larry Ellison, who has a net worth of $43.6 billion, to become the sixth richest person in the world.

"Our strategy is working and we have many more opportunities ahead. So we're going to keep investing to deliver more great results over the long term," said Zuckerberg.

The Facebook CEO, who at the age of 31 is the youngest in the top ten rich list, is also the fourth wealthiest person in America. At the earnings call, he revealed that people watched 100 million hours of video each day on Facebook, more than 1 billion people used FB Groups in a single month, and 80 million people use Facebook Lite, the service optimized for lower-bandwidth. He added that Facebook plans to keep experimenting with different ways to let businesses use Messenger.