I really like the simultaneous views of all variations and complementary colors in all the modes. Since you’re asking about tools, What I also like about my cu

I really like the simultaneous views of all variations and complementary colors in all the modes. Since you’re asking about tools, What I also like about my current go-to, http://paletton.com http://paletton.com is the URL dynamically changes the #hash to match the settings so you can just bookmark the page when you have things dialed in instead of clicking save. Also, you can vary the angles in the various complementary color modes.