The Problem With a 4-inch ‘iPhone 5′ Display

Recent rumours from Digitimes indicated that the next iPhone will sport a 4″ display and house a next-generation A5 chip. Other rumours from the WSJ hint at an iPhone ‘Nano’ with and ‘edge to edge’ screen. We won’t know if any of these come to life until they happen. But in regards to the 4″ display, TUAW breaks down the math as to why this won’t happen anytime soon:

To maintain 326 ppi, the pixel dimensions on a hypothetical 4-inch, 3:2 screen must increase to the neighborhood of 1080 x 720, plus or minus a few pixels.

…App developers would then have three sets of resolutions to support for the iPhone instead of two, and scaling from 960 x 640 to 1080 x 720 wouldn’t be anywhere near as simple as the pixel-doubling that got developers by in the early days before they were able to scale apps up from 480 x 320 resolution. Worse, any apps kept at a 960 x 640 resolution and “zoomed” to fill the new pixel dimensions would probably look pretty terrible; instead of doubling the pixels as happened in the early Retina Display era, the scale works out to 1 1/8 “zoom.”

So there you have it. For iOS developers, it’s hard enough to make that next ‘killer’ app. To support yet another resolution, that would further complicate the mix. What do you think?

[TUAW]