Free... Online painting and image editing platform.
Doodle Paint is a full featured painting and image editing platform providing users with versatile collection of tools and enabling users to contribute to ever growing community of doodlers with new features through plug-in.
You can change/add new features to Paint doodler by creating plugins. Paint doodler is written using HTML 5 java script. You need to follow some simple rules while packaging the plugin. Please refer to tutorial for details.