Rebelle has a feature that allows it to remember where the canvas is wet and where it is dry, allowing colors to blend together in an incredibly realistic fashion.
Rebelle primarily is used to create digital watercolor images like the one I did above. Out of the three programs I've looked, Rebelle is the one that emulates traditional watercolor the best. Rebelle has a feature that allows it to remember where the canvas is wet and where it is dry, allowing colors to blend together in an incredibly realistic fashion.