I have AsusWRT-Merlin running on my ASUS router.
I want to be able to connect and operate as a remote desktop to my NVS (home security system).
Would this be a good choice? droidVNC-NG
(OpenVPN, on the router, asks to import an .ovpn file - but I'm not sure about a source for that.)
Note: I've tried connecting via the Vanadium browser - but the NVS Gui refuses to play nicely (it's only friendly to microsoft hosted browsers).

UPDATE: I just need my GrapheneOS phone to function as terminal to the NVR.
Maybe RustDesk?
It seems that every app requires a computer of some sort in the middle.
Phone -> Router -> Computer -> NVR
Perhaps a dedicated RustDesk RaspberryPi?
Thanks!

I recommend setting up wireguard on the router if it is supported. Much more lightweight than OpenVPN. You can also check out tailscale.

Or maybe make the NVR Web UI publicly accessible via a reverse proxy but add mutual TLS authentication on the proxy, on top of the NVR authentication. Then you dont need VPN.

Installed RustDesk in GrapheneOS and on a dedicated RaspberryPi. - all good. Note: I had to switch from Wayland to X11 to fix a display problem, and to allow unattended remote login.
I'll look at hardening the install, next. Thanks!