Sales of devices based on Apple's OS X and iOS will overtake those of products running all flavors of Windows -- Windows 8, Windows RT, and Windows Phone -- in 2015, a Gartner analyst predicts. The switch in leadership would come roughly 13 years after Steve Jobs reinvented Apple, launching the iPod and plotting the company on a new path that has seen it conquer and define new markets, beginning with music players and continuing through cellphones and tablets.