I do a lot of oil painting in my spare time, and the iPad has become an incredibly useful tool for me in that effort. I use it for sketching and conceptualizing work without wasting paper or materials.
Attached below is a hi-res iPad painting I just finished recently. I use the Adobe Sketch app and have found it to be amazing at mimicking the textures of real pencils and brushes. I should also mention that I use the Apple Pencil, which this wouldn’t be possible without.
Here are a couple time lapses showing every gesture in the process: