During Apple's successful World Wide Developer Conference held earlier this month in San Francisco, Apple's CEO Tim Cook pounded home statistics proving that iOS is an incredible profit generating machine for developers. To back that fact up even further, a new report published by ABI Research today projects that the mobile app market will be valued at $27 billion in 2013 and that Apple's iOS is by far the leading OS in terms of profit. The stats claimed by ABI are staggering in stark contrast to reports that Android is the number one OS. In volume, Android may very well be the leading operating system in the world – but if you're a developer, Apple's iOS is the only game in town that will deliver home the profits needed to get ahead in this business. The statistical game of "Volume" is nothing more than a marketing shell game if it can't make developers money.