Though Apple Inc is selling enough iPhones to keep investors happy for now, the world's most valuable publicly traded company is set increasingly to rely on its apps and services to drive growth. Apple's services business alone - which includes the App Store, Apple Pay and iCloud - will be "the size of a Fortune 100 company next year," Chief Executive Tim Cook said on a post-earnings call on Tuesday. Revenue from the business rose 19 percent to about $6 billion for the third quarter, eclipsing sales of iPads and Mac computers for the second consecutive quarter to rank as Apple's second-largest unit after iPhones.