

If by this you mean you want to only rely on your smartphone then the local storage you want is just that. Get a good SSD that you can connect to your phone and carry it around. Then share your phone’s screen to a TV over WiFi or copy the file to your phone’s internal storage and plug it with an USB to HDMI cable if that’s an option for you. A good app on Android for file browsing is MiXplorer.
I usually only think about running stuff like Jellyfin when I’m already using my PC, so turning it on or off is never an issue and I’ll never need an external server for this purpose.
What OS do you use?