Great snippet from the NYTimes here–one that illustrates THE. MOST. IMPORTANT. PART. OF. PRODUCT. DESIGN.
Flurry, a mobile-software analytics company, estimates that 65 percent of all revenue generated in the App Store — roughly $2 billion — has come from free games that charge for extra goods. Peter Farago, vice president for marketing at Flurry, said that was partly because Apple had made it easy for people to buy goods within apps and charge them to a credit card on file with Apple.In contrast, Google has said that its app store, the Android Market, has generated little revenue. Mr. Farago said that was because making payments in the Android Market was more difficult.