There are almost too many to describe here with annotations, but I can list the one’s that I looked at:
doodle-buddy, auryn ink, bamboo paper, cpencils, inspire pro, noteshelf, notesplus, penultimate (evernote suite- really easy), quik sketch, skithc, hormonious, ddodlicious, notability, pen & paper, jot studio, pad board, tracing pari, dketchbook mobile, upad, sketchbook pro, brushes (finger painting), Jackson Pollock app
So Adobe ideas was covered in detail. It is basic, easy to figure out as there weren’t too many tools. One could use it as a coloring book if you have a black and white image saved to your computer.
Bamboo Paper. User can make one notebook for free, or many notebooks for $1.99. One can import a picture into the background of a drawing and export it too!
These are fun, and some have just too much and others not enough to bother- So my advice is PLAY. The beauty is in the X: you can always delete it!