Chris, there are not enough claps. Don't forget the QA process, API security and lots of other things too. The infinite hosting is a big one. Good luck finding a product from 2008 in your local Walmart.

27% is a steal. Its also not changed with inflation so as the value of currency has dropped, their cut has actually gone down for small businesses to 15%. Apple are not some saintly organisation but as far as the App Store goes they are fair.