I use Git; pass has integration with it out of the box (makes a commit for each change to the password store). I just push and pull periodically myself, but this could be automated. There is an Android app called Password Store that is compatible with pass and has Git integration built in.

I remember seeing some guy who had his `pass` Git repository public on GitHub and challenged the world to crack any of them. Myself, it's just git+ssh to a repository on my own server.