NEW YORK (AP) -- Research firm eMarketer expects spending on mobile advertisements to hit nearly $9.6 billion in the U.S. this year, up from $4.4 billion in 2012 and from less than $1.6 billion in 2011.
Mobile ads now represent nearly 23 percent of the money companies spend on digital advertising, or ads people see on their computers, tablets and mobile phones. That's up from about 12 percent last year and less than 5 percent in 2011.
Facebook, which began showing mobile ads in 2012 and Google, which has by far the biggest share of the digital advertising market, account for much of this growth.
EMarketer expects Facebook Inc. to surpass Microsoft Corp. and Yahoo Inc. when it comes to digital ad revenue this year, behind only Google Inc.