I’ve mentioned the GoodReader app several times in previous posts and wrote about it specifically here. Another one of those posts discussed digital document annotation on the iPad, where iAnnotate PDF was featured. The latest update to GoodReader adds annotation and other features to what is already a capable productivity app. You can now add highlights, notes, markups and drawings to PDF documents and save them in a PDF file that should work in most PDF readers on your computer. Marked up PDF files created in other programs are now readable.

Recall that GoodReader can also display content from many types of files, including MS Office, iWork, HTML, images, audio and video. You can transfer files to your iPad via USB, Wi-Fi, from e-mail attachments, or from popular cloud-based file services such as DropBox, Google Docs or MobileMe. The app is still just 99 cents, but the revised description warns this is an “introductory price” good for only a few more days.