The latest report from Quantcast shows that Apple's lead in mobile Web usage is declining.
The data, published Friday, shows that at the end of August 2010, iOS devices accounted for 56 percent of mobile Web usage in the U.S. The reason the chart is making news is because a year ago, iOS had closer to a 70-percent share. At the same time, Android use is growing. Quantcast shows Android's mobile Web share at 25 percent at the end of August, up from below 10-percent share a year ago.
Research In Motion devices stayed relatively steady at 9 percent, and "other" came in at 10 percent share.
iOS devices losing share is not exactly surprising. It's likely they'll continue to lose share of mobile Web use as Apple's competitors continue to churn out more Android devices. Quantcast counts iOS mobile devices as the iPhone and iPod Touch. The number of handset makers using Android on mobile devices is in the double digits--it's unrealistic to think Apple's mobile OS would continue to outpace the sales of many companies combined.
Put another way, iOS could only maintain its dominance in mobile Web use if every one of its competitors failed to design an even halfway-decent mobile device.