BlackBerry maker RIM was the biggest winner in a slowing smart phone market in the second quarter, roughly doubling its market share from a year ago to 17.4 percent, research firm Gartner said on Monday.

The market was still dominated by Finland's Nokia Oyj , which sold 15.3 million phones with capabilities such as e-mail and navigation, giving it a 47.5 percent share. But this was down from 50.8 percent a year ago as competition intensified in the consumer smart phone market.

"RIM continued to execute well at the consumer level, increasing its global market reach," Gartner analyst Roberta Cozza said in a statement.

Research In Motion sold 5.6 million smart phones in April through June, up from 2.5 million a year ago, as it found new clients beyond its main business market.

"In the second half of the year, the company is expected to launch smart phones based on new [designs] ... which are necessary to keep pace with the competition at the consumer level," she said.

Gartner said Nokia needs to introduce more design variations among its N-series multimedia phones to stay ahead. The company has only tweaked its N-series lineup so far this year and many analysts expect it to lose more market share in smart phones in coming quarters.

Credit Suisse said it expects Nokia's smart phone market share to fall to 41.6 percent in 2009, hurting profit margins.

New Competition

"Longer term, we maintain our concerns regarding smart phone share in the face of new competition from the likes of RIM, Apple and HTC (High Tech Computer)," analyst Kulbinder Garcha at Credit Suisse said in a research note.

Gartner said global smart phone sales growth almost halved from the first quarter to 15.7 percent.

"The current economic environment continues to negatively impact the market, limiting consumer spending and replacement purchases in general," Cozza said, adding growth should pick up again in July through September.

"Wider availability of new touch smart phone models together with the global introduction of the iPhone 3G will help sales of smart phones return to stronger growth in the third quarter of 2008," Cozza said.

Apple's share of global smart phone sales fell to 2.8 percent from 5.3 percent in the first quarter of 2008 as it sold down inventories of first-generation iPhones before the launch of the iPhone 3G.

High Tech Computer Corp (HTC) sales more than doubled from a year ago to 1.3 million phones, lifting the company to No. 3 position from seventh place the previous quarter.

In smart phone operating systems, Symbian lost market share as the Japanese market declined and Mitsubishi exited the market. Symbian had 57 percent of the market in the second quarter, compared with 66 percent in the same period last year.

RIM had 17.4 percent of the market and Microsoft's Windows Mobile market share stood at 12 percent in the quarter.