The worldwide boom in smartphones is defying the worldwide economic recession; globally, smartphone shipments grew by 13.4% in the second quarter. But the rollout of handset brands is proceeding at very different rates in different regions of the world, according to a survey from Canalys.

In the United States, Research In Motion dominates with a 52% market share of smartphones. However, the situation is fluid, as evidenced by the roaring success of Apple's iPhone, which has quickly captured 23.3% of the market. Sales of the iPhone jumped 365% in the second quarter, compared with the same quarter in 2008, according to the market research firm. RIM's shipments of BlackBerrys jumped 29% in the same quarter.

"RIM has successfully expanded its product portfolio to include a wide selection of devices and interfaces that appeal to a range of customers at different price points," said Chris Jones, Canalys VP and principal analyst, in a statement. "This includes 2.5G models that are smaller, lighter, lower cost, and have better battery life than most of its 3G rivals."

Also notable in the U.S. smartphone market was the market share decline of HTC, which dropped to 5.6% from 8%. Other brands, including those using Microsoft Windows Mobile software, also dropped.

Nokia, which has never had a major U.S. handset footprint, held onto its worldwide dominance, with a 44% market share. That was about the same share as it had in the year earlier, Canalys reported. RIM jumped to 21% from its 16.7% global share in the previous year. Starting from a more distant position, Apple nonetheless recorded a huge global year-on-year jump -- up 627%. The iPhone captured 13.7% of the global smartphone market -- up from 2.1% in the prior year.

Much of Nokia's strong position can be attributed to its heavy use of the Symbian operating system. Symbian OS still dominates with a 50.3% market share of smartphone operating systems. However, Symbian's share dropped from the 58.2% recorded in the second quarter of 2008.

"It is noteworthy how differently the smartphone business is developing compared to the PC industry," Jones said. "PCs are a highly standardized, commoditized platform where one model is often largely indistinguishable from another. Smartphones are different -- Nokia, Apple, RIM, and Palm have all achieved success by developing their own operating systems and delivering distinct devices and interfaces."

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