Canalys research announced today that in the first quarter the Chinese smartphone market surpassed the US market. China represents 22% of the world-wide smartphone market, while the US represents just 16% of the 145 smartphones sold. Apple's CEO announced at the Q1 conference call that sales of iPhones increased 5X from the same quarter last year. While Samsung is the number one smartphone in China, Apple comes a close second.
An interesting point in this article is that there are a plethora of Android app stores leading to a fragmentation of the app market in China. Google Play is generally installed by default on most phones.
Research Link: http://www.canalys.com/newsroom/china-overtakes-us-largest-smart-phone-market