[pertique]

It'd definitely be possible although, if you're not already using a VPN, I doubt it'd be easier. You could do it a few ways, but the gist would be running the VPN endpoint and the web app in the "same place" (same machine, same network, etc.) and restrict access to the web app from anywhere else.

[schemescape]

My thinking was that you could avoid setting up a domain and VPS as well. But you might be right!