There are thousands of applications on the App Store, and since the introduction of the Retina Display on the iPhone 4, many designers and developers have taken the time to up-res their applications for said display.
While I strongly recommend any and all developers to take some time to do this, I can understand that some restrictions or complications may hinder the goal of redesigning a ton of graphics, especially for games.
In lieu of this problem, I did a little thinking and experimenting.
But first, how does the Retina Display seem to make lower resolution applications more obvious than looking at an older iPhone display?
Answer: the “screen door” effect. When you look through a screen door, you see through the holes, and your brain fills in the missing information.
On the older iPhone display, not only were fewer pixels shown, there was also a visible gap between pixels. By drawing semi-translucent black lines every other pixel (both vertically and horizontally), I was able to simulate the lower resolution of the old displays.
I should note there is one side-effect to this, which may or may not come as a surprise to some of you: the screen looks slightly dimmer. Seeing as you can only really notice this when you see two images side by side, this is not much of an issue and frankly, I think its an acceptable compromise.
However, the result is sort of fascinating and intriguing. Again, while not a solution, it’s a workaround for developers on a tight budget or those who are spending their time on brand-new applications.
If you wish to download the Retro Display overlay image for use in your own application, you can download it here.