Readdle has released an update to its ReaddleDocs document viewer for the iPad, adding support for annotating PDF files. ReaddleDocs users can now add notes and highlights to PDF files which are saved within the document and can be accessed from a Mac or Windows PC. Users can also specify a color for PDF highlights, download files in the built-in browser by tapping on a link and open plain text files in a text editor. The update also improves WebDAV client compatibility with cookie-based sessions and resolves issues with unzipping certain types of ZIP files. ReaddleDocs for iPad is available from the App Store for $5 and is a free update for current users.