Hi,
I’m new to Roon - really like it so far. I saw some discussions on here about using Roon remotely through VPN’s, thought I should report that using Zerotier VPN could be a way forward with this. I can remotely control my zones over 4G fine using Zerotier - just not playback.
The Roon app seems to detect whether WiFi is being used on the iPhone and if not removes the iPhone as a player/zone and only allows zone control. I realise there might be some streaming difficulties with bandwidth but by using Zerotier it provides a true encrypted LAN extension so it would be nice to at least try and use it over 4G for playback. Zerotier ignores all uPnP nonsense and just provides a true flat LAN extension - its super cool but not really widely used in my experience. This would certainly allow laptops to access Roon very easily when remote without a lot of the usual VPN hassles and complexities.
Maybe a setting to allow playback without WiFi in the advanced settings would be enough?
Thanks!
Hi Steve, I managed to use ROON over 4G flawless - the ingredients:
a Roon Server connected to the internet, VPN-ish application on the server, port redirection on your router, default VPN on your iOS and than you can enjoy.
My scenario:
Router Draytek 2123 Fiber and forwarded these ports to the server
Service L2TP - UDP - 1701
Service PPTP - UDP - 1723
Service Roon Server - UDP - 9003
Service Roon UDP - 500
Service Roon UDP - 4500
Make sure the router does not have multiple L2TP and PPTP IPsec running to different machines this most likely interferes the setup (VPN)
Next on my Mac OS High Sierra Server 5.7 I installed VPN Enabler for High Sierra
https://www.cutedgesystems.com/software/VPNEnablerForHighSierra/ as far as I know on each Mac OS there is a VPN but not activated.
Of course if you want to go over internet your server (computer) needs to be connected and available on the internet. In my case I have a domain. it is not than most likely you will not get there 
Installing the Roon Server is easy - a few next buttons and you are up and running. But than the fun starts.
Installing Roon you can do it the easiest way but this did not work for me. I found out when you want to change ore switch to another Roon Core - you have to select HELP on the install screen - the program allows you to enter your domain name from your server and here (I think) the magic happens. By selecting The Roon Core with the external IP address or domain name as wel the internal IP address and external IP address are known by Roon. Next just follow the VPN Enabler for High Sierra instructions and add a VPN profile on your iPhone Use LPT2 protocol. and if everything is filled out accordingly you have a stable and nice remote connection to your Roon Server with Playback functionality and awesome sound. hope it helps a little?