In my opinion, the best drawing app out there for cartooning is Tayasui Sketches. It works great on the iPad and also comes in an Android version. Sketches just had a major update for the Apple Pencil. For 4.99, this robust little app will amaze wannabe cartoonists. I really love the zip-a-tone feature, you can create manga instantly without a headache. This is how Adobe should create a program for cartooning.