There is a tool that I have been using for years now without giving it much thought. It does a simple tasks of picking and applying of color. This illusory simplicity seems to have blinded me to the whole concept hidden behind it. I’m sorry Color Panel, let me redeem myself by telling people how to extend you.
Every Mac user is more or less familiar with the Color Panel, the small “Colors” window pops up in many applications when the user has to select a color. From text formatting in Mail, through shape editing in Preview, to storyboards or XIB customization in Xcode − most system apps make use of OS X Color Panel, and it’s even supported by a range of third-party apps, including Pixelmator or Photoshop.