Concepts, an iOS drawing app featuring an infinite canvas, sat untouched on my iPad forever ... What broke my mental logjam was the new Apple Pencil. Attached to the side of my iPad Pro, the Pencil is ...
Best canvas: Fredrix - See at Blick Fredrix ... but for any kind of pen, pencil, marker, or another drawing implement, it will do the job — it's a good thickness and weight.