While simply viewing or commenting on a PDF can be accomplished with free software, there are times ... it’s nice to be able to review and annotate files when you’re out and about.

So what I was looking for was a single app capable of pulling documents from Google, MobileMe and Dropbox, rendering them (even the large ones) with a crazy-fast engine and letting me annotate them.

There is a free PDF editor already available on ... move things around, and so on. The software also supports extensive annotation, including shape insertion, highlighting, underlining, striking ...

Annotate webpages in Safari using Markup to highlight text, add notes, and share edits seamlessly on your iPhone, iPad, or ...