[SaamanthaSterlyng]

The "Retina" display is a gimmick name, the human eye is still capable of perceiving individual pixels at the average distance you would use a tablet/phone. But the increased resolution allows for smaller text that is more legible, as well as more detailed images and GUI objects. Compare the APP icons on a iPhone 3g vs iPhone 4 and its a shocking difference.

We have both an iPhone 4 and a 3GS in the house. I know the difference.

Actually comparing screens I found that in the case of the iPhone 4 it was not only a bonus having the resolution but necessary considering that without it text would be intelligible on the iphone's tiny screen. (it's even much worse on the 3GS, having to zoom in all the time but that phone is practically from a different era now)

At the same time android phones had a lower resolution but the text is was still fine because they all have at least a 4" screen.