"How will apps scale?" wondered O'Donnell. "Apple is very particular about screen resolution." When Apple moved to a Retina-style screen for the iPhone 4, it quadrupled the pixel count by doubling the resolution in both dimensions, which resulted in a very smooth scaling for existing apps. For the iPhone 5 and its slightly-larger screen, Apple offered developers a stop-gap solution instead, one which used black bars to occupy the new real estate.
A move to phablet sizes, the experts said, could be eased by iOS 7, which introduced some resolution-independence to the OS, eliminating the need for costly, time-consuming updates to current apps.
O'Donnell expects that while iOS 7 will help developers adapt to changes in size or resolution, many will want to optimize their apps for the bigger screen. "That's why I think there's a good chance that this iPhone will be announced a fair bit before it's introduced," said O'Donnell, taking a page from Apple's 2007 playbook, when the company gave developers several months to build Web apps for the original iPhone.
"Apple's bread and butter is keeping the app developer community happy," concurred Llamas. "The size and resolution will be key considerations. The last thing Apple would want to do is put out an experience several steps back from what people are accustomed to. If Apple puts out [a larger iPhone] with a screen that looks like a 1980's video came, people will just say, 'We'll take a pass.'"
That wouldn't be good, not with Wall Street clamoring for something to drive substantial growth in Apple's revenue, the mantra for investors who have become disgruntled at the disappearance of the gravy train days when income soared and the stock price followed.
While those investors -- who are interested only in growth and pan Apple's enormous profits because they're not larger than before -- have told CEO Tim Cook he needs to find new product categories, whether iWatch or iTV or i-something else, a larger-sized iPhone would be the easiest and quickest sop.
"It's a classic case of better that they offer something, even if it eats their own children," said O'Donnell, referring to the chances that a larger iPhone will cannibalize sales of the now-hot iPad Mini. "To me, it's incredibly clear that this category [of larger smartphones] will shake things up."
But Apple, as always, will do things its way. Which could be very good for customers, if not enough to make Wall Street happy.
"Phablets are one reason why we'll probably see a larger-sized iPad," said O'Donnell. "It all fits together when you have choices from 3.5-in. to 12-in. for an iOS device, with the same experience across all those sizes."
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