People do form groups based on job, interests, gender etc. I have never heard of people forming groups based on mobile OS.
Correct- groups are formed based on age, gender, culture, socioeconomic background, interests, etc
And surprise, surprise, a single mobile platform tends to dominate in each one of those groups.
Example: 88% of teens in the USA have an iPhone. Guess who teens text the most...other teens…lol