Vision-based, human-computer interaction technology is mature to substitute legacy physical devices such as mouse and joy stick for a number of different applications. Yet, some sort of mistrust prevents them from being used mainly because - in the past - the main focus has been on the computer vision side and not on usability, reliability and efficiency of the interface. This paper introduces a vision-based perceptual user interface (PUI) applied to radio-controlled (RC) mobile units. Its main effort is on shifting the research focus from basic computer vision and image processing issues to ease and naturalness of use, integrability and compatibility with the existing systems, portability and efficiency. We believe that current technologies can easily support vision-based PUIs and that PUIs are strongly needed by modern applications, but more effort is needed to merge the knowledge from HCI and computer vision …