TwoToJazz offers two line brushes for drawing, sketching, and doodling. Nothing exciting or unusual there, except that TwoToJazz allows you to copy/multiply an arbitrary line that you draw into a more complex object that you can then copy and multiply recursively to create complex objects from simpler ones. Please use this feature judiciously as complex objects get heavy and maybe slow to move! Try multiplying by holding one finger from one hand on the screen and moving one finger from your other hand moving around the other finger, like drawing a circle with a math compass. You can create all sorts of fantastic objects using this technique.