He basically concludes that non-iPhone development has huge sunk costs (i.e. less competition), so it is where the money is:
"The bar is set too low. Anybody can play in the iPhone space. All it takes is an idea and few thousand dollars to pay someone to build it. The entire process, from idea to launch, takes only six weeks.
In my world--the Sprint, T-Mobile, Verizon, AT&T world--a game costs $50,000 to build and $100,000 to port."