I use dropbox with Zotero almost every day. You can get them to play together relatively easily, using Dropbox for syncing pdfs, and your Zotero account for syn

I use dropbox with Zotero almost every day. You can get them to play together relatively easily, using Dropbox for syncing pdfs, and your Zotero account for syncing the references. This was my initial motivation for using Zotero, as other reference managers, such as Mendeley, which made not using Mendeley's storage very difficult. It is very convenient to be able to add references at work, then come home to find it all up to date on my home PC. Dropbox integration with the camera on my phone is something I also use a lot. Take a photo of something in the lab, it is waiting for me on my PC by the time I am back at my desk. The only thing that I really find lacking is a linux armhf cli client...