The human tongue has superior movement and tactile sensations. For individuals with severe disabilities, a tongue operated interface device can be used to operate life-support equipment, such as powered wheelchairs and robotic manipulators. A joystick-type device can directly translate various tongue motions to external equipment behavior. In addition, the user can interactively communicate with the equipment by tactile feedback. This helps the user to control the equipment safely and skillfully. Considering these factors, in a previous study [1], we developed a novel tongue-operated joystick device with reaction force feedback mechanism. We described the design process including the analysis of human tongue movement and tactile sensations and showed fundamental performances of reaction force feedback with the prototype device. In this study, we discuss the shape of the operational part that is used by the tongue. Two types of operational tools are prepared and their operability and perception of reaction force feedback are compared. Furthermore, we confirm the effectiveness of reaction force feedback to operate the joystick device safely and skillful controlling a mobile robot in an unknown environment.