I have a Mac and a number of art apps.
Of the apps I own, the Morph works with Art Rage and Mischief and Pixelmator.
It, disappointedly, doesn’t currently work with Corel Painter Essentials (I have version 5, 6 is the newest) or Rebelle (an app that simulates watercolors). Both those apps don’t recognize the Morph’s pressure sensitivity at all. I had purchased both of them before I got my Morph, assuming they would work with the Morph.
I also have an older version of Corel Painter (version 12) and it doesn’t recognize the Morph’s pressure sensitivity at all either.