Worldwide sales of smartphones to end users grew by a record 30% year-on-year during the fourth quarter of 2014 to 367.5 million units, according to Gartner.
Apple grabbed the top spot from Samsung, which had been market leader since 2011. Apple reported its best quarter ever, selling 74.8 million units.
Apple's strong ecosystem and its new iPhone 6 and iPhone 6 Plus drove strong replacements within the iOS base, Gartner said. These new smartphones also offered new users, who are looking for larger screen phones, a strong alternative to Android.
For the full year 2014, sales of smartphones to end users totalled 1.2 billion units - up 28.4% from 2013 - and represented two-thirds of global mobile phone sales.
"With Apple dominating the premium phone market and the Chinese vendors increasingly offering quality hardware at lower prices, it is through a solid ecosystem of apps, content and services unique to Samsung devices that Samsung can secure more loyalty and longer-term differentiation at the high end of the market," said Roberta Cozza, research director at Gartner.
Chinese vendors, such as Huawei and Xiaomi, are continuing to improve their sales in China and other overseas markets, increasing their share in the mid to low-end smartphone market.
"They are producing higher quality devices with appealing new hardware features that can rival the more established players in the mobile phone market,” said Cozza. “Brand building and marketing will be key activities in deciding which Chinese vendors can secure a foothold in mature markets."
The availability of smartphones at lower prices also accelerated the migration of feature phone users to smartphones pushing the smartphone operating system market to double-digit growth in most emerging countries, including India, Russia and Mexico.
This trend continued to benefit Android, which saw its market share grow 2.2 percentage points in 2014, and 32% year-on-year.