Try Color Lib

[Morbix]

Chameleon is a lightweight, yet powerful, color framework for iOS (Objective-C & Swift). It is built on the idea that software applications should function effortlessly while simultaneously maintaining their beautiful interfaces.

With Chameleon, you can easily stop tinkering with RGB values, wasting hours figuring out the right color combinations to use in your app, and worrying about whether your text will be readable on the various background colors of your app.

https://github.com/ViccAlexander/Chameleon