Apple Q4 profit up 31% on iPhone sales but outlook seems muted

New York

APPLE on Tuesday turned in another quarter of enviable revenue and profit growth, fuelled by sales of the iPhone. But the results raised a perennial question for the world's most valuable company: How can it keep its growth streak alive?

The issue was stoked by Apple's muted forecast for its all-important holiday quarter, as well as the unwillingness of Timothy D Cook, the company's chief executive, to go into detail in an earnings conference call about how Apple plans to rev up sales next year.