Record notes & audio at the same time. Better yet, have the audio synced with your notes. Insert text, drawings, photos, & highlight notes.

A productivity app giving you anytime access to all your important Google Docs.

From the popular flashcard website Quizlet.com, their official app is available.

A two window reader/browser for the iPad with Dropbox support.

From Evernote, Skitch allows you to annotate images & documents with arrows, stamps, shapes, text, & more. Annotate a PDF & photo.