Your NAS won't be on your home LAN so could be, as far as I'm aware from the brief details, in a business enviroment where security policy could prohibit it. So my suggestion may not be possible in your situation, depending there for on what your situation is.In my situation??
Ok cheers, I will have a look at that app.
People are doing this so it must be possible.
If you have a Synology NAS, you can get the SynoDS app from the App Store, its excellent, does everything you want and more
Oh and no VPN here, external IP on Router, forward all traffic from external port to internal LAN Address of NAS, works a treat.
just tried this... fantasico appGot this working in the end using an App called Filesconnect. I set it up as an AFP server and it connected to my NAS first time