Signs have emerged that demand for the cheaper iPhone 5C is lagging the iPhone 5S both of which went on sale in September because its $100 discount is proving to be insufficient to motivate emerging market and price-conscious customers.
But some analysts say the concerns are overblown and that a greater proportion of iPhone 5S shipped, translates into better margins and earnings overall.
Apple will be reporting results just a week after taking the wraps off an incrementally improved iPad Air. But it is the iPhone, which accounts for more than half the company's profit and is its highest-margin gadget, that takes centre stage.
Apple is expected to report sales of 33 million to 36 million iPhones in its fiscal fourth quarter that ended in September, rising to more than 50 million in the typically strong holiday quarter the first full quarter of sales of the two new phones.
Media reports of 5C production cuts are misleading, in our view, given what we think has been strengthening overall 5S/5C production with 5S vectors continuing to strengthen even real time, Timothy Arcuri, an analyst at Cowen & Co, said in a research note.
Apple has come under pressure over the past year or two to bolster sales of its iPhones and iPads as perennial rival Samsung Electronics and cheaper gadgets based on Googles Android software chip away at its once-leading market share.
Its stock has gained 12.5% since August, when activist investor Carl Icahn disclosed a large position in the iPhone maker and began making calls for a new, stepped-up $150-billion share buyback programme boosting hopes of a bigger return of cash to shareholders than anticipated. But the stock is still down about 1% this year.
Longer-term, investors wonder whether the company that revolutionised the cellphone industry and popularised the tablet computer has another groundbreaking device left in it.