The patterns of usage in each city often reflect economic stratification. For example iPhones, in red, are predominantly in wealthy sections of the city while Android phones, in green, have more coverage in poorer sections. On a global level, national trends reveal a complicated set of cultural preferences.
I wouldn’t say this is surprising – simply another data point demonstrating what we already know… iPhone owners have more disposable income. It explains how the iOS is more profitable as a platform than Android.