The design, use, and performance of edge-scrolling techniques

Edge-scrolling techniques automatically scroll the viewport when the user points near its edge, enabling users to reach out-of-view targets during activities such as selection or drag-and-drop. Despite the prevalence of edge-scrolling techniques in desktop interfaces, there is little public research on their behaviour, use or performance. We present a conceptual framework of factors influencing their design. We then analyse 33 different desktop implementations of edge-scrolling by reverse-engineering their behaviour, and demonstrate substantial variance in their design approaches. Results of an interactive survey with 214 participants show that edge-scrolling is widely used and valued, but also that users encounter problems with control and with behavioural inconsistencies. Finally, we report results of a controlled experiment comparing four different implementations of edge-scrolling, which highlight factors from the design space that contribute to substantial differences in performance, overshooting, and perceived workload.