EdgeSplit: facilitating the selection of off-screen objects

Devices with small viewports (e.g., smartphones or GPS) result in interfaces where objects of interest can easily reside outside the view, into off-screen space. Researchers have addressed this challenge and have proposed visual cues to assist users in perceptually locating off-screen objects. However, little attention has been placed on methods for selecting the objects. Current designs of off-screen cues can result in overlaps that can make it difficult to use the cues as handles through which users can select the off-screen objects they represent. In this paper, we present EdgeSplit, a technique that facilitates both the visualization and selection of off-screen objects on small devices. EdgeSplit exploits the space around the device's borders to display proxies of off-screen objects and then partitions the border regions to allow for non-overlapping areas that make selection of objects easier. We present an effective algorithm that provides such partitioning and demonstrate the effectiveness of EdgeSplit for selecting off-screen objects.