(Bloomberg Businessweek) -- In 2011, when Apple Inc. Chief Executive Officer Tim Cook wanted to show off the first major product under his leadership—the iPhone 4S—the company invited Epic Games onto the stage. Mike Capps, Epic Games Inc.’s president at the time, made a quick joke about how much money his company’s games made from Apple devices. Then he helped run a demo of Infinity Blade II, designed to showcase both Epic’s new game...