Now that the third generation iPad has been released, rumors are starting up about the new iPhone (iPhone 5? the “new” iPhone?). Apparently there’s been some information ‘leak’ that’s started the rumor that the new iPhone will have a bigger, 4.6-inch Retina display.

Of course, we see no facts from anyone proving that this is true. Nor are most people putting much thought into the consequences of changing the dimensions of the iPhone in such an extreme way. John Gruber (at DaringFireball.net) made a great point,

“…this new iPhone would need way more pixels than the current 960 × 640 iPhone display. (If they increased the size but kept the pixel count the same, it would drop beneath Apple’s “retina display” threshold — not going to happen.) That means every app in the App Store would need to be redesigned/resized.”

My math may not be perfect, but going from a 3.5-inch diagonal to a 4.6-inch diagonal doesn’t quite double the area of the screen. So in order to keep the new iPhone at Retina quality, Apple would have to add a quite odd amount of pixels. Updating the graphics in apps for developers wouldn’t be as simple as doubling the resolution. As Gruber said, they would likely have to redesign almost every app in the app store.

My guess: 4.6-inch screen? Not very likely. Chalk this up as another reason we don’t traffic in rumors.