Why are Google and Facebook banned in China? If Google is banned, then how do Chinese phones have Android?
Google and Facebook are banned so it give space to local players like Sina, Baidu and Tencent to develop into billion dollars companies. Also, the government can keep better control of the information that circulates and easily monitor user data as they have full control on China-based services.
About Android, China is actually lost to Google as the Google Play market is closed. All Chinese phone brands ship with Android *without * Google, like Xiaomi that use a fork called MiUI. So Google makes zero revenue from ads or apps on Android in China. In many cases, you have to flash the phone to enable Google apps. They are many other different app markets available in China and constructors usually pay themselves with it. Android still used as the main OS because it is free and easy to implement esp since it comes with full ARM support.
This text was originally published in quora.