Does proprioception guide back-of-device pointing as well as vision?

We present research that investigates the amount of guidance required by users for precise back-of-device interaction. We explore how pointing effectiveness is influenced by the presence or absence of visual guidance feedback. Participants were asked to select targets displayed on an iPad device, by touching and releasing them from underneath the device. Another iPad was used to detect finger positions from the rear. Results showed that participants were able to select targets as accurately without visual feedback of finger position as they were with it. Additionally, no significant increase in workload was identified when visual feedback was removed. Our results show that users do not require complex techniques to visualize finger position on the rear of device. Visual feedback does not affect any performance parameters, such as effectiveness, perceived performance, and the number of trials needed to select a target. We also outline the implications of our findings and our future work to fully investigate the effect of visual guidance feedback.