Educated forecast points to 750x1334 pixels panel for the 4.7" iPhone 6, 1242x2208 resolution for the 5.5-incher

When Apple changed the iPhone's screen resolution for the first time with the iPhone 4, it went for exactly double the horizontal and vertical pixel count of the predecessor, without causing much trouble for developers. Later on, when the inevitable happened, and the iPhone 5's screen diagonal grew to 4 inches, Apple just increased the vertical resolution count, leaving the 640 horizontal pixels intact, which led to banding effects in some apps, but most were quickly rewritten for the new resolution anyway.

Now, with the rumored upcoming 4.7" and 5.5" ...