FineScanner can do the same basic things the other free apps do: take a photo and turn it into a PDF. You can also share the scan easily and upload to a large number of cloud services. Like most other apps mentioned the premium features are locked behind a paywall.
The stand-out feature of the app, Bookscan mode, will cost you money as well. It's supposed to be able to automatically split an open book into two different images, eliminate page curves, and get rid of other imperfections (like dogear creases). Using Bookscan mode will cost you $2.99 for permanent access to just that element of the app, or Bookscan and other premium features can be accessed through the $4.99 monthly fee.