The iPhone 5 has a 4-inch Retina Display. It is the first iPhone from Apple to have a screen with a size other than 3.5 inches. Until now, the iPhone 5S was expected to keep the same size and design as the iPhone 5. Citing Asian suppliers, Bloomberg and the Commercial Times say Apple has chosen to increase the size of the iPhone 5S's display from 4 inches to 4.3 inches. Apple will still call it a Retina Display, but there's no word if Apple will alter the resolution from the iPhone 5's 640 x 1136 pixel screen.
The veracity of the report is questionable for several reasons. First and foremost, Apple CEOs Steve Jobs and Tim Cook have long maintained that the reasoning behind the iPhone's small screen (compared to its competitors) is to improve one-handed use of the device. Cook has reiterated several times this year that Apple will not compromise usability just to improve the iPhone's spec sheet. Many devices with screens 4.3 inches and larger can be difficult to use one-handed. Phablets with screens larger than 4.7 inches often require owners to use both hands to reach all the on-screen controls.
[ Is it time for Apple to lower the walls surrounding its OS? Read Apple Must Look Beyond Its Platforms. ]
Second, the report conflicts directly with others published this year about the iPhone 5S. The Wall Street Journal, for example, suggested in June that the iPhone 5S will be similar to the iPhone 5, but with improved internal components. In fact, photos published of supposed iPhone 5 parts appear to be identical to those of the iPhone 5, helping to corroborate reports such as the Journal's.
Further, Apple has been very consistent at releasing two iPhones with the same form factor back-to-back, such as the iPhone 3G and 3GS, and the iPhone 4 and 4S. Based on Apple's repeated patterns, it stands to reason that the iPhone 5S will have the same form factor of the iPhone 5. (Of course, Apple can always change its behavior.)
Last, such a delay would be incredibly risky for Apple. The company has introduced no new "i devices" this year: there's been no new iPad, iPod, or iPhone since last fall. The lack of new products has led investors to question Apple's product strategy. Apple's leaders have reassured investors several times that the latter months of the year will be crammed with new products. Pushing the expected September or October release of the next-gen iPhone to November or December could be disastrous to Apple's financials.
Will Apple ever increase the size of the iPhone's screen? Possibly, but probably not this year.