According to research firm International Data Corporation (IDC), Apple's sales of 20.3 million iPhones worldwide during the second quarter of 2011 helped the company secure 19.1 percent market share and lead above all other smartphone vendors.
Apple's shipments grew 141.7 percent compared to the second quarter of 2010, when it sold just 8.4 million iPhones and secured a 13 percent share.
Samsung saw its shipments grow 380.6 percent over the last year to remain steady at 17.3 million in the second quarter and was able to secure a 16.2 percent market share.
Samsung credits its success mainly to the company's high-end devices, such as the Galaxy S and Galaxy S II, which sold three million units in its first 55 days on the market, IDC said.
"What originally began as a series of high-end smartphones has proliferated well into the mass-market, but has not strayed too far from its high-end roots," International Data Corporation wrote about Samsung in its report on smartphone shipments. "Moreover, its steady cadence of device releases and updates has kept Samsung's smartphones well out in front of the competition."