There has been an ongoing rumor that the new upcoming iPhone is expected to have a 4.2-inch panel screen. Now there is a new report by DigiTimes that reports the panel size will be less than 4 inches.
Another rumor is that the back design will be changed to a metal chassis instead of reinforced-glass. Other specs that are rumored for the new iPhone include a 4-4.2-inch HD touch panel screen, 8 megapixel camera, full HD video recording, A5 dual-core processor, and a then design.
The reason why the new iPhone would have a smaller panel would allow the phone to be thinner and for the screen to appear larger.