As Nokia continues to shed market share, second-place Apple is inching closer to become the world's dominant smartphone vendor, according to IDC's latest Worldwide Quarterly Mobile Phone Tracker.

For the first quarter of 2011, iPhone maker Apple shipped 18.7 million smartphones, up from just 8.7 million a year ago, helping it capture a record number of shipments for a single quarter. Apple's growth was boosted by triple-digit gains in China as well as in the the U.S. with the debut of the Verizon iPhone. Continuing its expansion, Apple also picked up South Korean Telecom and Saudi Telecom as two more iPhone carriers across the globe.

Nokia led the worldwide landscape by shipping 24.2 million smartphones, up from 21.5 million a year ago. However, the Finnish phone maker continued to drip market share, now accounting for 24.3 percent of all smartphones sold, down from 38.8 percent in 2010's first quarter.

Demand for Nokia's Symbian phones remained robust in its core markets of Europe and Asia/Pacific. But even as more Symbian devices are set to hit the market, including Nokia's E6 and X7, IDC believes the company may further lose market share as it transitions from Symbian to Microsoft's Windows Phone.

BlackBerry maker Research In Motion also increased its shipments last quarter but shed some market share to the competition, now owning a 14 percent slice of the market. Though RIM has unveiled a variety of new 3G handsets, it's still stuck shipping a large number of older, lower-cost phones, IDC said, a move that's expected to continue into the next quarter.

Android device makers Samsung and HTC rounded out the top five list of global smartphone vendors as both companies experienced dramatic growth in both shipments and market share.

Samsung saw particularly strong demand for its high-end Galaxy S-class phones as well as its Galaxy Ace and Galaxy mini devices. But its Windows Phone 7 and Bada Wave devices also showed promising growth in the marketplace.

HTC captured a record number of shipments for the quarter, aided by a number of new devices that were able to tap into 4G across different carriers, including the Inspire 4G, the Evo Shift 4G, and the ThunderBolt.

Overall, the global smartphone market jumped 79.7 percent last quarter, triggered by a greater variety of models at lower prices combined with nonstop consumer demand. Shipping 99.6 million units for the quarter, the industry almost doubled its numbers from the 55.4 million shipped a year ago. And the dramatic growth shows no signs of slowing down.

"Conditions in the smartphone market are creating a perfect storm for sustained smartphone growth," IDC senior research analyst Ramon Llamas said in a statement. "First, vendors are increasingly emphasizing smartphones as the key to their own growth. Second, selection has proliferated from mostly high-end devices to include more mid-range and entry-level offerings. Third, pricing has become increasingly competitive, with even high-end devices available at low price points."