PDF Expert 6 came out today and I discovered that it had a simple URL scheme for opening PDFs. Adding pdfe to the beginning of a web URL will launch PDF Expert and the PDF is imported.

There is a simple trick to automate this process and that is to create a Javascript bookmarklet. I keep the bookmarklet in the tool bar of iCab and when I want to import a PDF I will just select the bookmarklet. The bookmarklet is: javascript:location.href='pdfe'+location.href