4-Inch iPhone: Possible Scenarios

Chatter about an iPhone with a larger screen has been going on since the pre-iPhone 4S days, but this time around these claims have been backed by reliable sources like The Wall Street Journal, Bloomberg and John Gruber.

Apple has always held pride in the fact that iOS is easy to develop for, and that it isn't fragmented like Android. Even when it upgraded to Retina displays, it made sure that the number of pixels in the new screens were a whole number multiple of the previous screen resolution.

So how is Apple going to ensure a similar, smooth transition phase for developers with a larger screen iPhone?

That first thought that comes to mind is that Apple simply increases the physical size of a single pixel, so as to maintain the same (current) Retina resolution of 960x640 pixels, and make the transition process a breeze for developers. This would however reduce the pixel density of the new screen to a figure below 300ppi, which would force Apple to pull off the Retina tag from the new device. Retina, of course, isn't merely a bullet point in Apple's marketing strategy, it also makes text, images and video on the display look gorgeous. Given that, we don't expect Apple to go along with this option, which not only degrades the current iPhone experience, but also makes developers' work practically nil. (After all, Apple hasn't hesitated in the past to ask developers to put in a bit of effort to make the whole iOS experience a lot better.)

Another possibility came from a person named Timothy Collins, a caller on one of Verge's podcast. His idea -- keep the width as well as the number of pixels along the horizontal the same as before, and increase the aspect ratio to 9:5 from the current 3:2, adding pixels along the vertical so as to make the diagonal 4 inches and maintain the same pixel density of 326ppi at a resolution of 1152x640. Gruber speculated that Timothy wasn't merely speculating, but was in fact basing his ideas on actual knowledge he has about Apple's plans.

Here's how apps will look on such a screen. If Apple does go with this option, iOS would most likely take care of rendering standard app layouts like lists, navigation bars and tab bars on the larger screen, but developers would nonetheless have to work on producing their images at this resolution. Game developers on the other hand would have face the uphill task of rendering their graphics at a completely unrelated resolution.

Rene Ritchie over at iMore has some more interesting scenarios, some of which are:

• Proportionally scaling the existing iPhone screen to a diagonal length of 4 inches, bringing the resolution to 1092x728 pixels.
•  Increasing the resolution to the industry standard 1280x720 pixels (720p), increasing the pixel density to 367ppi.

He's illustrated all the possible scenarios with mockups, and thought about the ramifications of each of these choices. You should read through the entire post.

It looks like Apple would have to deal with a small degree of fragmentation issues with a 4 inch iPhone, but it could hope for no further changes in this size for quite a few years, meaning that iPhones with older configurations would gradually be weeded out from the market. Besides, this scenario is still better than the one at the Android camp, where no one has any control over what screen sizes could manufacturers possibly float in the market.

It  will be interesting to see how Apple handles the challenge of the 4-inch screen for the next iPhone and the 7-inch iPad, both rumored to debut later this year.