An original equipment manufacturer (OEM) human-machine interface (HMI) device operation of a non-OEM handheld mobile device is provided. A non-OEM handheld mobile device can be coupled with a vehicle network of a vehicle. The vehicle can include a head unit with a display. An OEM HMI can be presented on a display of the non-OEM handheld mobile device. Thus, the non-OEM handheld mobile device provides functionality associated with the head unit and/or functionality not associated with the vehicle. Responsive to receiving an input on the OEM HMI presented on the non-OEM handheld mobile device, a setting or control of a vehicle device can be caused to be adjusted. Alternatively or in addition, responsive to receiving an input on a vehicle OEM HMI, a setting or control of the non-OEM handheld mobile device can be caused to be adjusted.