We are entering the third age of Apple. A PC company first, and now very much the trillion-dollar iPhone company, Apple Inc. is evidently in search of its next big thing. Speculation about what that might be runs rampant every time a new Apple skunkworks project is revealed, be it a self-driving car, a health-care push or a pair of augmented-reality goggles.
While the services that come paired with iPhones are themselves a substantial and growing part of Apple’s revenue, they will continue to need hardware to lock in customers....