Frontier runs on your own computer, but that doesn't mean you have to be sitting at it. Remote Access, in the account menu behind your avatar, shows a QR code — scan it from your phone's camera while on the same network, and the same install opens there. Not a copy, not a cut-down version: the same workspaces, the same threads, the same agents still running on the machine at home.
It is the ordinary use that makes it worth setting up. An Agent finishes something while you're out, and you can read what it did, answer the one question it got stuck on, and let it carry on — from the kitchen, or the train.
The connection is encrypted, using a certificate this install generates for itself. The first device to connect shows a one-time warning that the certificate isn't from a recognized authority, which is exactly what you'd expect for a private connection between two of your own devices — tap through it, and you're in. To stop it appearing at all, "Trust this machine" installs the certificate here, and a second QR code installs it on your phone; after that, every future connection is silent.
If the machine has more than one network connection, pick the address your phone actually shares with it from the dropdown. And nothing here opens anything to the wider internet — it is your own network, and your work stays on your own machine, as it always does.