I want to import a PDF into my iPad2. It will be a map which I can draw over and annotate. I want to be able to save it, without destroying the original, so I can draw over the same map/template repeatedly. I'll then mail or transfer the annotated PDF to my computer. I have Goodreader, but I haven't found any instructions on saving versions.I know there are dozens of APPS out there which will very ably allow you to annotate over a PDF. I haven't been able to determine if any of them will allow me to save versions of the PDF and keep the original. Can anyone suggest an APP which will meet my needs?