Question: I have a huge collection of PDF. Mostly it consists of research papers, of self-created documents but also of scanned documents.

Right now I drop them all in one folder and give them precise names with tags in the filename.

But even that gets impractical, so **I am looking for a PDF library management application**. I am thinking of something like [Yep](http://www.ironicsoftware.com/yep/) for Mac, with the following features:

* PDF cover browsing (with large preview, larger than Nautilus allows)
* tagging of PDF (data should be readable cross-platform)
* possibility to share across network (thus rather flat files than database)
* if possible: cross-platform

Mendeley seemed to be a good choice, but I am not only having academic papers and don't want to fill it all metadata that is required there.

The only alternative I could find thus far is [Shoka](http://www.mauropiccini.it/shoka/), but the features are limited and developments seems to have stopped already.

Answer: 
Have you Tried Gnome Documents?

> 
> GNOME Documents is a standalone application to find, organize and view
>  your documents.
> 
> 
> 

![Documents](https://i.stack.imgur.com/Fyfa8.png)

[![Install via the software center](https://hostmar.co/software-banner)](https://apps.ubuntu.com/cat/applications/gnome-documents)
**[Referencer](http://packages.ubuntu.com/de/lucid/referencer)** (GNOME) is a simple tool for managing document collections. 

Tagging is possible.

It tries to find metadata on arXiv or via DOI, but you can add metadata manually too, of course.

But I guess development stopped.