Only with the right hardware. Most phone remote apps for Android TV and Google TV, including The Remote and Google's Google TV app, work over Wi-Fi, so your phone and TV have to be on the same network. Without Wi-Fi, you need a phone with an infrared (IR) blaster, or a Bluetooth connection your TV supports.
Wi-Fi remotes need your phone and TV on the same network
Google's own phone remote says it plainly: your phone and TV must be on the same Wi-Fi network. Google's virtual-remote checks Internet on both devices isn't enough. They have to be able to reach each other on the local network.
An IR blaster works without Wi-Fi, if your phone has one
A few phones have an infrared emitter, like a classic remote. With an IR remote app and the right profile for your TV, they can send basic commands with no network at all. Most phones don't have one, so check your phone's specs first.
Bluetooth is another route on some TVs
Some apps connect to Android TV over Bluetooth as a remote or keyboard. Whether it works depends on the TV, and setup usually starts in the TV's remotes and accessories settings, which means you need a way to reach that menu first.
Guest, hotel and office Wi-Fi often block phone remotes
Even when there is Wi-Fi, networks that keep devices apart (client isolation) or need a sign-in page can stop a phone from finding the TV. On someone else's network, ask the owner. Don't switch off security settings. Google's network guidance
The TV lost its Wi-Fi and you have no remote
That's the awkward loop: the TV needs a remote to rejoin Wi-Fi, and a Wi-Fi remote needs the TV on Wi-Fi. The lost remote guide covers the ways out: buttons on the TV, HDMI-CEC and a USB keyboard.
The Remote needs your home Wi-Fi
The Remote is a Wi-Fi remote. Your Android phone (Android 8.0 or later) and your Android TV or Google TV (with Android TV Remote Service v2) need to be on the same home Wi-Fi. It's free, with no ads and no account.