The drawings here are partly analog (pen and paper), partly digital (iPad). Even a "pencil drawing" can be implemented much better on the iPad, because the Apple Pencil can accept any number of pencil modes and above all, because you can zoom quite unrestricted into the details of the drawing.
On the other hand, it is still fundamentally different to draw with a real pencil on real paper than with the digital equivalents - much like the feeling of holding a real book in your hand and reading it differs from the feeling of holding a digital reader.
