Apple typically supports the last 3 generations of an iOS device. When the next iPhone (5?) comes out, 3GS and its 480x320 screen will get pushed out, leaving only 4/4S and the 960x640 resolution. That opens up the opportunity to introduce a new resolution*. The current iPhone has a pretty thick bezel, which gives some room to increase the screen size without increasing the physical phone size. Here's how three potential screen sizes stack up in terms of physical size. Note that even the 5" screen is still about the same size as the total size of the physical iPhone 4S... If they can get rid of the bezels completely. *dreams* --- This is the screen of iPhone 4/4S: I've noticed that if you increase its width by 25% and height by 50% you get: Coincidence? You tell me. The reason I didn't multiply the width by 50% is because it becomes too wide for fingers to grip. But there's no reason not to increase the height more. Well, it changes the aspect ratio of the screen of course. If you wanted a more boring/conservative 25%/25% increase in both directions, you'd get this. --- *iPhone Apps would have to be updated to support the new resolution. Old apps would be displayed in the 3.5" middle part of the screen (no smaller than on iPhone 4S screen) with black borders, or scaled by 1.25x to fill screen. Similar to how iPad 1 ran iPhone apps in 1x or 2x mode.