According to the May 11 report "Global Smartphone Vendor Market Share by Region: 2008," the iPhone OS will be the second fastest-growing smartphone OS in the U.S. 2008, by 79 percent, and RIM's BlackBerry OS will be the second-largest overall smartphone OS.
Android's shocking growth will be thanks in part to encouragement by vendors, developers and operators, according to the report.
"The Android mobile operating system from Google gained early traction in the United States in the second half of 2008 and it is gradually spreading its presence into Europe and Asia during 2009," according to the report.
The study also credits Android's relatively low-cost licensing model, semi-open-source structure and support for cloud services, in addition to manufacturer support from HTC, Motorola, Samsung, T-Mobile, Vodafone and others.
"Android is now in a good position to become a top-tier player in smartphones over the next two to three years," said Strategy Analytics director Neil Mawston in a statement.
The study also notes that RIM's BlackBerry OS pulled ahead of Microsoft Windows Mobile to become the second largest smartphone OS in 2008.