Investigating How Smartphone Movement is Affected by Body Posture

We present an investigation into how hand usage is affected by different body postures (Sitting at a table, Lying down and Standing) when interacting with smartphones. We theorize a list of factors (smartphone support, body support and muscle usage) and explore their influence the tilt and rotation of the smartphone. From this we draw a list of hypotheses that we investigate in a quantitative study. We varied the body postures and grips (Symmetric bimanual, Asymmetric bimanual finger, Asymmetric bimanual thumb and Single-handed) studying the effects through a dual pointing task. Our results showed that the body posture Lying down had the most movement, followed by Sitting at a table and finally Standing. We additionally generate reports of motions performed using different grips. Our work extends previous research conducted with multiple grips in a sitting position by including other body postures, it is anticipated that UI designers will use our results to inform the development of mobile user interfaces.