Facebook's biggest challenge and its greatest opportunity now lies in mobile devices. Most Facebook users access it using a mobile phone or tablet computer, but the company only started showing mobile ads about 9 months ago.
Facebook said it generated 23%, or $306 million, of advertising revenue from mobile, up from 14% in the third quarter.
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The French president has delivered posthumous awards in a national ceremony in Paris as the slain officer's partner appealed for peace.
One mother said she had travelled for hours to celebrate her daughter's 16th birthday, only to miss the gig completely.
The family of a former Royal Navy officer who was killed as thieves stole his car pay tribute to the 'wonderful husband, son, and brother'.