You can draw on an iPad with an Apple Pencil on the Procreate app, which you can use to sketch, paint, and illustrate.

Glen Southern demonstrates how to use Procreate with 3D reference models to speed up your concept art workflow.

After a while, I moved on from tracing to drawing from a reference image placed beside my canvas. Here, I was aided by Procreate’s grid lines and its color picker — a feature that lets you ...