Moleskine Smart Notebook - Turn hand-drawn sketches into fully workable vector files
Documents by Readdle - A central hub for all your files.
Action Method Notebooks - Notebooks for making ideas happen
Lunamaker - Lunamaker is a paper notebook with digital courses on drawing and sketching.
Notebook.ai - A smart notebook that grows and collaborates with you
PDF Professional - PDF Professional is a feature-rich PDF Ultimate Solution for reading, annotating, form filling, editing, signing, and converting PDFs on your Mac, iPhone and iPad.