The country's mobile phones shipments in the second quarter reached 87 million. Of those shipments, 51 percent, or 44.4 million, were for smartphones, according to data provided by IDC on Friday.

Smartphone shipments were originally forecast to overtake feature phones only by 2013, said Teck Zhung Wong, an analyst with the research firm.

"The market has really exploded," he said. "People are really buying into smartphones and prices have come down quite a lot. Mainly due to lower prices, more devices can be bought at a cheap price, but still perform very well."

Driving most of China's smartphone sales are those priced at 1000 yuan (US$158) and lower, Wong said. At the same time, Chinese retailers are less interested in carrying feature phones, and instead want to sell smartphones.

In the second quarter, Samsung's smartphone market share was the highest at 19 percent, according to IDC.