This new “Retina 2” display would take advantage of the device’s enlarged screen, seeing the smartphone adopt a 5.1 inch display, compared to the 4-inch (diagonal) widescreen multi-touch display the smartphone carries, today. This screen, the concept suggests, would also be capable of receiving and storing energy from the sun, (via the use of solar power), but the smartphone itself would retain the same body size.
Very thin iPhone 6 (iPhone Air) concept
Here is a pretty cool concept video with the iPhone 6, or iPhone Air (if it will be called that). It looks very very thin, but I like the design :)