https://www.theverge.com/2018/5/17/17366662/steam-link-android-beta-valve-pc-game-streaming-service-launch

Valve announced earlier this month that its Steam Link game streaming service would be coming to mobile by the end of May, and now we have a beta version on Android to play around with. The app is live on Google’s Play Store starting today, and it will let you stream full PC games via Steam so long as the smartphone is connected to a nearby PC through a 5GHz Wi-Fi network and the PC is connected directly to your router with an ethernet connection. For now, it seems that you won’t be able to use Steam Link over LTE.

You’ll be able to play games on mobile using the Steam Controller and presumably any other Bluetooth gamepad device, which includes the Xbox One controller and other Android-compatible devices. (Valve hasn’t yet released a full list of supported controllers._ The app will also work on Android TV set-top boxes, so long as your Android TV is connected directly to the same router as your gaming PC. Valve says the app should support 4K at 60 fps, but that 1080p at 60fps will be the standard quality bar for most titles, according to Variety.