Looking for an app to make corrections to screen color on iphone 5

[JimP]

A while back I found an article about how accurate the iphone 5 display is but there were differences from sample to sample.

I then found where someone had a jailbreak program where you could make slight adjustments to correct any off color on the screen. The problem they were fixing was that some were experiencing screens that were slightly yellow. With this program, they could neutralize the yellow by making adjustments to RGB (red, green and blue).

Does anyone know how to make that adjustment either native to ios 7 or a program within the apple apps store. I don't want to go down the road of jailbreaking as you're at the mercy of the next apple update.

Thanks,

Jim