This app takes a directory with PDFs and outputs a corresponding directory that contains the same PDFs labeled with groupings based on the text of the PDFs. It also supports renaming of PDFs based on some of the initial text so that your research papers don't have to be named by number.
This is useful for research papers from arXiv that tend to come in a numbered format for the downloaded PDF. Using the renaming option of this Mac app you can then end up with a useful name for the file plus a useful rename.
It lets you go from the following files
And get the following: