The mobile advertising firm's April 2009 AdMob Mobile Metrics Report also includes figures from Gartner that estimate iPhones made up eight percent of all smartphone sales in 2008.
Gartner's figures also show that Symbian handsets were the most popular, accounting for 52 percent of all smartphones sold. However, AdMob says Symbian users only account for 26 percent of mobile web traffic.
The report also revealed that smartphones running Google's open-source Android platform, such as the T-Mobile G1, accounted for less than one percent of all smartphones sold but generated more that three percent of all mobile web traffic.
When it comes to HTML browsing from mobile phones, Apple's iPhone remained the most popular device, account for 65 percent of all traffic. It was closely followed by Android devices which generated nine percent of all traffic and in third place were handsets running the Symbian platform, which made up seven percent of all traffic.