We all know that removing the background from watercolor illustrations is not so easy. Normally I do it in PS, but I wanted to figure out how this works on an iPad. Nic explains everything in this class and it's really easy. From now on I will only use my iPad because it works so well. I'm not satisfied with the pattern, but I understood how to make it and next time I can recreate it.
The original watercolor illustration with the cold-pressed background: