Colorpicker is efficient through its interface. Every features are accessible from the toolbar and shortcuts. You have the possibility to choose any color thanks to the three RGB sliders (soon HSL, CMYK, ...)!
Pika (pronounced pi·kuh, like picker) is an easy to use, open-source, native colour picker for macOS. Pika makes it simple to quickly find colours on screen, in the format you need, so you can get on with being a speedy, successful designer.
ColorPicker is a professional color creator and picker which has advanced features for artists and designers. It is written with C++ and Qt for the best performance and flexibility.