Viewing Web sites on cellphones isn’t a mass pastime in the U.S. quite yet. Screens are tiny, download speeds are often slow and fees can pile up. Yet a sliver of people — about 15% of U.S. cellphone users, according to research firm M:Metrics Inc. — do surf online via their phones, checking out entertainment, news and other sites. The experience is similar to surfing the Internet via a personal computer, except the number of sites that are fashioned for cellphone screens is much smaller. The owners of these sites have a supply of viewers, and there is plentiful demand among advertisers to reach young, tech-savvy people.
AdMob and another upstart, Third Screen Media, act as middlemen in the business. Advertisers need these companies’ help in harnessing technology to deliver an ad on a phone without glitches. Site owners often prefer to turn their supply of ad space over to middlemen rather than trying to beat the bushes for potential advertisers.