From what I understand, Retina displays are simply a screen with a high PPI (higher than that of your eye at "optimum viewing distance"). Why, then, do applications need to fix their interface to ...
Is there any negative adverse effect to optimizing images for retina screens, if the images aren't exactly double size?
For example: Say I have an image that is going to be displayed at 1000px wide. I want to optimize my site for retina displays, but the largest resolution image I have to put here is only 1900pixel ...