From Ben Thompson at Stratechery:
This is a very big deal. Feel free to ignore anyone making snarky comments about China’s average monthly wage being the same as the price of an iPhone 5C. The two pertinent facts about China are that:
There is tremendous income disparity There are a TON of people
So while many Western markets may have a greater percentage of the population that can afford an iPhone, the absolute number of Chinese who are potential customers is very high as well.