• by Mark Walsh  @markfwal, February 7, 2011

Smartphone shipments worldwide increased 87% in the fourth quarter to 100.9 million from a year ago, fueled by surging Android phone and iPhone sales. For 2010, total shipments rose 74.4% to 302.6 million, according to data released today by technology research firm IDC.

Both Samsung and HTC saw triple-digit growth in the fourth quarter, with unit sales up 439% and 258%, respectively, by following a strategy of selling multiple Android devices. Samsung enjoyed the biggest gain in market share among the top five smartphone vendors in 2010, nearly tripling its share from 3.3% to 9.6%. The manufacturer will build on the popularity of its Galaxy line of Android devices this year by adding the Galaxy Fit, Ace and Mini phones. The goal is to grow its share 40% in 2011.

HTC, which nearly doubled its share from 4.5% to 8.5% last year, will also try to sustain its momentum by becoming a preferred brand for smartphones and increasing business in the Asia/Pacific region and other emerging markets.

With iPhone unit sales increasing 87% in the fourth quarter, Apple's market share among smartphone makers has held steady over the last year at about 16%. But the company continued to close the gap with No. 1-ranked vendor Nokia, which has seen its share fall from 38.6% to 28% in the last year.

Last week, research firm Canalys issued a report saying that Android had overtaken Nokia's Symbian as the world's top-selling platform in the fourth quarter, selling 32.9 million devices compared to 31 million Symbian-based phones. Apple, by contrast, should get a further boost in 2011 by adding Verizon Wireless as a U.S. carrier partner. Wall Street analysts have estimated Verizon will sell 11 million iPhones in 2011.

Nokia and No. 3 smartphone maker Research in Motion (RIM) both increased shipments 36% in the quarter. But like Nokia, RIM's market share has continued to tumble, from 19.9% a year ago to 14.5% at the end of 2010.

Android "has become the cornerstone of multiple vendors' smartphone strategies and a challenger to market leader Symbian," said Ramon Llamas, a senior research analyst at IDC. "Although Symbian has the backing of market leader Nokia, Android has multiple vendors, including HTC, LG Electronics, Motorola, Samsung and a growing list of companies deploying Android on their devices."

What about Windows Phone 7, the upgraded version of Microsoft's mobile operating system launched last fall on Samsung, HTC and others? IDC said Windows Phone 7 devices "ramped up quickly" in time for the holidays, with shipments of more than 1.5 million units. Phones with Nokia's refreshed Symbian^3 platform had also gained traction, shipping more than five million units. But with the holidays over, both will have to prove they can maintain growth through 2011.