Make abstract images à la Mondrian or Rothko.
Create beautiful colour schemes.
Or just zone out.
Colorian creates random images within a small number of constraints set by you: colours constructed from red, green, and blue components, proportions of those colours, and the size and shape of the colours boundaries.
This is a free product, made for fun. Please do contact the developer with love and hate messages and, of course, share the app and its images.