Google's Android mobile operating system has found an unlikely source of support in China in spite of the internet search giant's recent threat to pull out of the country – hundreds of small “grey-market” Chinese phonemakers which are now trying to become legitimate manufacturers of more advanced devices.

Political uncertainty about Google's status in China has already led to the delay of two high-profile Android phone launches last month, which analysts say could hurt confidence in Android's development in China.

But in the southern Chinese city of Shenzhen, the hub of Chinese phone manufacturing, a very different business dynamic is driving small phone manufacturers to adopt Android. While Microsoft and Nokia both charge phonemakers for the use of their operating systems, Google provides Android for free.