Ask HN: How do you organise papers / documents / articles coherently?

I use Pocket to save web-based articles, but have an increasingly cluttered collection of PDFs which I fully intend to read (or at least reference) but never get around to it. Some of these are from emails, slack, downloads, and some are available online.

Pocket really doesn't work well for PDFs.

I'm looking for a good solution to storing a library of PDFs and documents so I can read them in a queue, find them later, etc.. It would be great if articles and PDFs and documents could all live in the same place, but for now ¯\_(ツ)_/¯.

Even better would be something portable across my Mac, Linux machines, iOS, etc..

How do you all keep track of PDF documents and save them to read later?