Till now I always coded my interfaces this way:
I considered a retina screen as half its actual pixels, giving all interface positions the same number of pixels as it was let's say (ipad) a 1024x768 screen, but throwing in all png images as downscaled 0.5%. I mean, the button that should appear 40pixel on a 1024, needs to be a 80pixel png, so the retina will show it in all its definition. A 40pixel button will be upscaled.
Iphone 5 is behaving differently, images in there are like it was a 1136 x 640 actual screen. It was not doing this 3 months ago... ??!?!?! HELP.
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