making a game in a phone

in my phone game, i have an app called “jump” and that is going to be turned into a game. How do i make it so when the “runner” moves the phone doesn’t move away and it looks like the game is in the phone? Sorry for the bad explanation of what i want. Ask questions if you need more info. Thanks!

Put the phone gfx into the User Interface layer.
That will stay in place like a fixed window, like a picture frame.