TrinusVR Lite is an app that allows you to transform your typical Android device into a real virtual-reality device you can use with your PC games. The only thing you need is a Google Cardboard, or another similar device, and to have the TrinusVR client installed on your computer.
Setting up TrinusVR Lite for the first time can be a little complicated, but once it's ready on your PC, you won't have any trouble using it with any of your video games. That said, because of the limitations in the Lite version, you can only use it for half an hour at a time.
It's best to use TrinusVR Lite wirelessly, but if you have problems doing it you can always connect the device via USB, with which you typically get a better performance.
TrinusVR Lite is a great and inexpensive way of enjoying virtual-reality in your games. Obviously the results don't match that of Oculus Rift and other similar devices, but the price is far lower as well.