Lead paragraphs from a timely snapshot of OneNote apps/services, which are all free; also see Microsoft brings its digital ink to the iPad with OneNote handwriting update (The Verge)
"OneNote is the best Microsoft program from you’re probably not using. If you’ve ignored the digital note-taking app because, well, it’s Microsoft, or because you thought “the last thing I need is more software,” then it’s time to reconsider.Microsoft OneNote tutorial: Everything you need to know to start taking notes
Microsoft has liberated its digital notebook from Office and put it just about everywhere: Mac, iOS, Android, Chrome, and of course Windows. Read on to discover everything you need to know to start creating a paperless life with OneNote."