Display Test Pro
This program is a collection of various simple and more advanced tests, which can be used to investigate iPhone Retina display performance and propriety.
Also with this app you can understand display physics, view cool tests, adjust brightness and learn new things.
Optimized for iPhone 4, 4s, 5, 5c, 5s
This app is identical to Display Test app + 4" devices support and new user interface with cool animations.