▼Types
Pens are suited for line drawing.
Comic pencil
Sketch pencil
Classic pencil
Felt tip pen
Brushes are suited for coloring.
Hard brush
Soft brush
Flat brush
Watercolor
Oil pastel
▼Adjusting the size
You can change the brush/pen size using the slider.
▼ Eye dropper tool
Dragging the tool over the image and doing a long press will pick up the color it's hovering over.