Cocoa Point vs Pixel and PPI

Question

Well, I have basically two questions regarding screen resolution in iOS devices.

1) In iOS documentation, on the Point vs Pixels section, it states the coordinates a

Answer 1

On retina devices (iPhone 4, 4S, or 5, and iPad 3 or 4), there are 2 pixels per point. On non-retina devices, there is 1 pixel per point.

Except for the iPhone 5, all iPhones have a screen size of 320x480 points. The retina iPhones have a screen size of 640x960 pixels (but the same point size as the non-retina devices).

When working with images in iOS, it is the pixel size that matters, not the PPI. Just remember that your @2x images should have twice the width and height of the regular, non-retina images.