Comparison of off-screen visualization techniques with representation of relevance on mobile devices

When exploring map information on mobile devices, relevant points of interest (POIs) are often located off-screen. Despite the existence of several techniques that allow the exploration of the surrounding areas, none represents the POIs' relevance. Furthermore, when the number of POIs increases, the visualization of the information often becomes unintelligible. This paper presents: our approach to enhancing off-screen visualization techniques with the representation of relevance and cluttering reduction; and a comparative study, using three modified techniques with the proposed approach, HaloDot, Scaled Arrows and Mini-Map. We concluded that while Scaled Arrows has advantages when analysing the distance to the most relevant objects, the Mini-Map provides better information about the distribution of the POIs, helping users on navigational tasks. Also, the choice of an off-screen technique depends, at least, on two factors: number and geographic distribution of POIs.