Nokia intends to boost its mobile ad business through the acquisition of Enpocket, which provides mobile phone marketing technology and services to advertisers, Web publishers and carriers.

Nokia announced on Monday that it has entered into a definitive agreement to buy Enpocket, whose technology platform and business partnerships Nokia expects will allow it to rev up its products and services in mobile advertising, a market poised for robust growth. The companies did not disclose financial terms of the deal.

After years of great promise and unmet expectations, mobile advertising is expected to boom in coming years, going from a tiny market to a considerable one.

Last week, The Kelsey Group predicted that spending on mobile search and display advertising in the U.S. will hit US$33.2 million this year and grow at a compound annual rate of 112 percent through 2012, when it will total US$1.4 billion.

Kelsey Group also expects the number of mobile Internet users to grow at a 20 percent compound annual clip in the U.S. through 2012, when there will be almost 92 million people going online via their cell phones.

Worldwide, mobile ad spending is expected to reach US$1.5 billion this year and grow to US$11.3 billion by 2011, according to market researcher Informa Telecoms & Media.

As mobile phones become a viable vehicle for online marketing, all major telecom, online publishing and Internet players are jockeying for position in this market.

Those pursuing the mobile ad opportunity include online service giants like Google and Yahoo; US mobile carriers like AT&T and Verizon Wireless; and handset manufacturers like Apple Inc. and Nokia.

Nokia expects to close the Enpocket acquisition in this year's fourth quarter.

Enpocket, based in Boston, offers the Enpocket Platform, which the vendor describes as a "carrier-grade mobile campaign management and delivery system" designed for operators, advertisers and publishers. It has customers in Europe, Asia and the U.S., including Vodafone, Pepsi, Telefonica, AT&T, British Telecom and Sprint.

Eden Zoller, an Ovum analyst, wrote in a note e-mailed to the media that Nokia does well in acquiring Enpocket, because the company is a strong mobile advertising specialist whose technology platform has a solid analytics component. "Enpocket gives Nokia a leg up in mobile advertising and credibility that it needs to be taken seriously in the space," Zoller wrote.