Philosophical research in mobiquitous devices still lacks important topics, in particular how mobiquitous devices change us and our perception of the world. It is the aim of this paper, to make a basic contribution to this debate and to shed some light on fundamental questions. Therefore, we introduce the TANIA system, a tactile acoustical navigation and information assistant for the blind, which uses - among other concepts - 1) a vibrating Wii remote mounted to a cane so as to indicate for the orientation of the blind towards a certain destination and 2) a stereo camera integrated into a bicycle helmet so as to compensate for the loss of vision. Alteration of perception is discussed in detail by distinguishing between perception enhancement, perception substitution, perception constriction and perception determination. Moreover we elaborate upon basic system design issues, thereby also justifying why we designed the TANIA system like it is. Finally, it is shown that technology itself has never been something else but an extension to man, and that technology - since technology is not only a means but also a medium - has always altered, still alters, and will always alter our perception of the world.