The Copic color system is a curated listing of colors in the Copic marker set which carries 300 or 400 different shades. Each shade of the Copic color marker had a number on it identifying the exact color so you know what shade you use in your artwork. Sketchbook Pro has this and I miss being able to simply choose from that grid of colors. It made choosing colors so easy because I could then switch to the regular color Swatch and choose a more exact shade. I hope Artstudio Pro could get this.