Yahoo today will unveil a deal with mobile services provider Bango that is designed to make it easier for businesses to buy paid search listings on cell phones.

IAC's Citysearch also is preparing to launch a new mobile search offering next month. Already, Citysearch rolled out a "send2phone" feature that allows users to send themselves text messages of phone numbers and street addresses for listings, in preparation for the new service.

In addition, Google last week said it was testing a new service that allows search marketers to distribute pay-per-click and pay-per-call ads to mobile phones in the United States, the U.K. and Japan.

The new services are all coming just as mobile content and advertising is poised to grow. Last week, The New York Times upgraded its mobile service by making the entire Web site available on mobile phones and PDAs with Web-surfing capabilities. Research firm and conference organizer Informa Telecoms & Media late last week released a report predicting that mobile ad spending will climb to $11.35 billion worldwide by 2011. Mobile TV revenue alone grew to $85 million in the second quarter, according to research firm Telephia (see related OnlineMediaDaily story).

While the entire mobile content field is expanding, the increased attention to mobile search specifically is the natural outgrowth of the success of paid search on the Web, said Greg Sterling, principal analyst at Sterling Marketing Intelligence. "Obviously, it's the evolution of the online marketing model extended into a mobile context," he said.

Through the Yahoo-Bango deal, Bango will create mobile presences for businesses that want to purchase paid search listings for display on mobile phones, and will manage Yahoo Search keyword campaigns. Bango also will be able to provide back-end analytics about mobile search campaigns.

Sterling added that the Yahoo-Bango deal appeared likely to especially appeal to sophisticated brand marketers that already bid on keywords for Web search.

The deal will go live in the United Kingdom by the end of the year, and will launch shortly afterwards in Japan and the United States, said Michael Bayle, senior director, Yahoo Search Marketing.

Separately, Yahoo also is conducting beta tests of a mobile search service in the United States. That initiative involves Yahoo distributing paid search listings to mobile devices through a partnership with go2, which operates a mobile directory of local business and movie information.

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