I set up tailscale on my jellyfin box and my family can use their phone to access the server by turning on tailscale (just open the app and toggle it on then open jellyfin) and cast to their Tv. Not as smooth as plex but works for us and the tailscale means its all encrypted.

I run it on a raspberry pi4 that is also my pihole and after turning off transcoding its runs beautifully. Running in a docker container. With 1tb ssd attached via usb 3 the whole setup cost me about £100 and has been working for about a year now.