As an end user I approve of the walled garden. I don't mind the limitations on other forms of payment. I think it helps prevent fraud and insecure transactions, and I like the freedom and ease of use that comes with knowing that apps on the ios store went through a fairly substantial review process. As a developer (though it has been a few years since I wrote code for mobile) Apple's tools, documentation and librarie…
Interestingly, that's about the average income tax rate. I wonder if Apple and Uncle Sam both independently came to the same conclusion that that's the highest amount that they can get away with without hitting the tipping point.