With the shutdown of Stadia, you might have a physical Stadia controller laying around gathering dust. Don't worry: It's not just an expensive paperweight. If you play games on other systems, you can use your Stadia controller with other platforms. Here's how.
You didn't need Google's own Stadia controller to use the service. It was only required if you're playing Stadia on a Chromecast Ultra. The controller could be purchased separately, or you could get it with the Premiere Edition subscription.
If you happen to have the Stadia controller, you might be interested in getting more use out of it. Unfortunately, the controller can only be used wirelessly for Stadia. The controller's built-in Bluetooth connection is only used when you're setting up Stadia. When you're playing Stadia, the controller connects over Wi-Fi.
The good news is that Google designed the controller to work as a standard USB HID controller when it's plugged into other platforms. USB "HID" means "Human Interface Device." That's the same classification as keyboards and mice. Like those devices, the Stadia controller will pretty much just work when you plug it in, no setup or proprietary drivers required.
What that doesn't mean is that every game will support the controller. The buttons might not match up correctly, and you might need to do some configuration to get it just right. In general, though, USB HID controllers work out of the box for many PC games.
The Stadia controller comes with a USB-C to USB-A cable. The USB-C end goes into the controller, and the USB-A end goes into the console. That's all there is to it.
At the time of writing, the Stadia controller can be used to play non-Stadia games on PCs and on Android phones and tablets (via USB adapter). It doesn't appear to work well when it's plugged into gaming consoles (such as an Xbox or Playstation 5).
If you have a Stadia controller lying around collecting dust, it's time to put it to use playing some games on your PC. It's a little frustrating that Google doesn't allow it to be used as a standard Bluetooth controller, but wired compatibility is better than nothing.