Earlier quoted context omitted.
For the same reason that every other app developer out there works on iOS versions first: you make more money that way. iOS customers spend more money and buy more apps.
Maybe the developers have a Macbook and know iOS? And if we're going to talk metrics, at the rate that Google Play spending has been exploding, it will be passing the iOS ecosystem sometime very shortly. By no stretch am I saying that anyone should target Android instead of iOS, but right now if one hits one or the other it is primarily driven by skillsets and not some objective evaluation. Ideally toolsets and skill…
Once Google Play actually passes iOS, feel free to make that point. Not before.
As a recent employee of various startups and established companies in the mobile space, I can tell that you that the only pattern I've witnessed here is:
a) decide what to develop for based on the market
b) hire people that can develop for that platform
Not the other way round.