Global UI elements are present throughout the Android Auto system and cannot be modified by app developers. A consistent interface creates more predictable experiences for drivers so they can better focus on the road.
Applications must use the global UI and not replicate existing Android Auto system functionality. For example, applications that require a drawer must use the Android Auto drawer and not build a custom launcher that navigates to many levels of hierarchy. Android Auto apps that break or interfere with the core system UI will be disabled or degraded.