A head-mounted display (HMD) system includes an HMD device wearable upon a head of a user, and a peripheral device that is dockable with the HMD device via a pair of electronic connectors. The HMD device and the peripheral device may communicate with each other via wireless communications in a docked configuration, and may communicate with each other via wired communications over the pair of electronic connectors in the docked configuration. The HMD system supports a variety of different modes of operation that may be varied responsive to whether the peripheral device is in the docked configuration or the undocked configuration with the HMD device.