I would like to be able to create a rainbow brush. I use that option in the Colorest app.This adds a neat affect to the picture.
My two year old loves coloring on this app (and so do I). He suggested a rainbow color option - as in the ink comes out in rainbow form. Thought it was a neat idea. Perhaps it could be an added option next to each pallet to “color” in all the colors of the pallet at once. Great for your younger audience and also may give a cool tie dye effect - I hear that’s in these days!