In June 2008 20.8 million US and 4.5 million European mobile phone subscribers accessed search - an increase of 68 and 38 percent from June 2007, respectively. The UK had the highest penetration of mobile subscribers using search at 9.5 percent, followed closely by the US at 9.2 percent, according to comScore.
"It is interesting to note that as we see the number of mobile search users increase, the frequency of activity is also growing," observed comScore analyst Alistair Hill.
The number of people accessing mobile search at least once a week grew 50 percent in Europe, with France and Spain leading at a rate of 69 and 63 percent, respectively.
Meanwhile, the number of US users accessing mobile search has more than doubled as a result of expanded 3G penetration (especially with the Apple iPhone 3G) and smartphone adoption, as well as the proliferation of flat-rate data plans.
Google is the preferred brand for browser-based searches with a 60 percent share of mobile searchers ("mobile searcher penetration") in all countries measured by comScore M:Metrics.
Yahoo! ranks second in Germany, Italy, UK and the US. In the US Yahoo's mobile searcher penetration is 34.6 percent, more than double its share in most other countries.