The one reservation is that, while apps propose to be able to add meta-data to PDFs, I think that only Acrobat Pro to my knowledge also allows one to edit the alternate text and tags to internal links.
PDFExpert lacks any ability to edit links. It also gets some of the meta-data wrong compared to Acrobat Reader (and I’ll be filing a bug report to Readdle when I have the time).
Honestly, before I would invest the time to go through any route that uses multiple apps, I’d just purchase Acrobat Pro and be done with it.
As far as LaTeX specifically, some folks are working on pdf tagging packages that will work within the LaTeX engine itself. But, as I have learned, this is a huge undertaking for LaTeX that would almost be better served with a re-write of the LaTeX kernel itself. As somewhere someone said, LaTeX is far behind in the PDF world view.
I believe the absolute best option is to use Acrobat Pro. I know of no other options that are reliable to the standards that Adobe requires.
When you would use LaTeX, it supposedly has a package or two that will allow you to munge-about to manage the XMP tagging that you need. I didn’t have the appropriate level or super-powers to decode them readily.
This doesn’t actually help answer this specific question/thread, but figured I would post here since this post is what I found when looking up how to covert to PDF/A (needed to do it for uploads to NSF). Hopefully sometime in the future someone gets some help (and that person might be me this time next year).
Good to know. I’ll pass this information forward to our technology teams at our university. The topmost link also has a wealth of links to convert to/from various formats. This is a good resource for students in COVID/REMOTE courses.
FWIW< I did a quick test with a document that had an underlying PDF issue (a bug in an old LaTeXiT equation). The file converted to a PDF/A format. But the formatting issue did not go away.
In short then … First make sure that Adobe Reader DC reports no errors with your PDF. Then convert it to PDF/A.
I feel like Stephen with searching how to do something and coming across my old post as the solution. I’ll probably be back here again next year for the same search for the same annual report. Also, I realize that I didn’t procrastinate quite as much last year for a report due in April.
I have since discovered how to create PDF/A in LaTeX. Use either hyperxmp or (perhaps better) pdfx (shout out to @JohnAtl in case you are listening for PDF/A compliance for your ARCHIVAL LaTeX documents). Also as far as I can determine, PDF/A is a metric to certify the document is fully self-contained (e.g archival). It is not a metric on whether the document has any ADA compliant tags. I have also since decided that tackling an ADA issue should best remain recognized as being well beyond my pay grade, time, and return on investment.