Google just announced a new game streaming service called Stadia, which promises to deliver 60 fps gaming at 4K. You will be able to use existing USB controllers with Stadia (or mouse and keyboard), though Google has designed its own custom controller with a couple of unique buttons.
The first of those is a capture button. Pressing it will making sharing content to YouTube quick and easy. You can also use this button to save content for yourself, or to share with friends (perhaps through Facebook and Twitter, though Google did not go into detail here).
There is also a Google Assistant button, because this is Google we are taking about, so naturally it is pushing its own digital assistant. When you press the button, it fires up the controller's built-in microphone so you can talk to the Assistant. If a developer has implemented any features specific to Stadia, the Google Assistant will be your gateway to accessing them.
"This is your gateway to the best of Stadia," Google's Phil Harrison said during the company's keynote at GDC 2019.
Beyond those two special buttons, the controller sticks to the usual script—it has shoulder buttons, a pair of thumbsticks, a D-pad, and a design that looks sort of like a hybrid between an Xbox One and DualShock 4 controller. It will connect to the cloud through Wi-Fi.
As with the service itself, Google has not yet announced pricing or availability for its controller.
Source From:https://www.pcgamer.com/this-is-googles-custom-controller-for-its-stadia-streaming-game-service/