Use your iOS device as a gamepad
1 Switch to Game Mode
When playing games, a gamepad icon appears right above the trackpad. Tap it to switch the app to Game Mode, which strips away the extra controls that can’t be used for games and orients the others in a landscape, gamepad-like layout.
2 Buttons for gaming
Game Mode places the large, grey trackpad on the left of the screen, and two buttons on the right. Those buttons are equivalent to Select and play/pause on a Siri Remote, or the A and X buttons on an Apple TV gamepad, respectively.
3 When you’re finished
Tapping Close returns to portrait mode with all controls showing, and stays in the game – handy if it insists on that orientation for menu navigation. Menu also returns to portrait, but suspends the game and goes to Apple TV’s main menu.