Terminology

Term Description
Stroke A stroke is the result of a painting action on the painting support, it starts when you push Pencil on the iPad surface, it ends when you left it from the painting surface.
Forward Painting  
Backward Painting  
Color Pattern  
Pick Up Gesture It is a gesture to pick up some color from painting surface. This gesture can be used for Knife and Brush.
Painting Tool It is a mandatory tool to produce directly the artwork such as Brush, Knife, Tube, etc.
Sgraffito

Sgraffito a technique used in painting, which consists of putting down a preliminary surface, covering it with another, and then scratching the superficial layer in such a way that the pattern or shape that emerges is of the lower colour.

Impasto Impasto is a technique used in painting, where paint is laid on an area of the surface very thickly, usually thick enough that the brush or painting knife strokes are visible. Paint can also be blended right on the support. When dried, impasto provides texture, the paint appears to be coming out of the canvas.
Oil Painting Medium