Wondershare PDFelement can help you convert any PDF (even one created from a scan) to any format, as well as allow you to edit, annotate, or sign it. It is an excellent partner for business or study, or for editing forms for a trip. It's an excellent alternative to Adobe Acrobat.
Note: price reflected on the listing is for the "Pro" version of the app.
Note: The downloadable demo is version 6.8.0; the version available for purchase on the Mac App Store is version 6.7.12.