Staring at a reference image, trying to figure out how to get those exact colors into our materials? This add-on basically lets you do that. Draw over any image and it picks up the colors and assigns it to a color ramp.
Want a simple 3-color fade? Cool. Need 20 stops to capture every single shift in that reference? Also cool. Set the amount of color stops and choose your preferred sampling method and the add-on will take care of the rest.
Just select a ColorRamp node in your shader editor, load a reference image in the Image editor, then click sample gradient and start drawing. It's that simple.