PSP world: "Apple's iPhone has been a tremendously successful product. It has facilitated Apple's entry into two challenging new markets: mobile phones and video games. By all accounts, the Cuppertino California company has been successful with both ventures. The iPhone sold more than 10 million units last year, and users have been quick to embrace paid downloadable content through the Apple App Store. Many of the most popular applications downloaded from the store, according to recent statistics, are video games."