3D Touch in Smartphones

Objective: The purpose of this research is to identify whether or not 3D Touch is conflicted with long press when 6 different levels of threshold pressures are applied, to explore the reasons. Background: Though problems arising when applying both 3D Touch and Long press on smartphone are predictable, related researches were limited. We investigated the difference between the manners when users are pressing for 3D Touch and when users are pressing for Long press to understand the reasons for this problem. Method: Total 30 smartphone users participated in this research. All participants tested 3D Touch and Long press interaction using iPhone 6s Plus. A software recorded the maximum pressure, time to reach the maximum pressure and error rates. Results: The result was shown that the time to reach the maximum pressure is increased as threshold pressure is increased in 3D Touch interaction. In the analysis of error rate, it was shown that error rate is increased for 3D touch and it is decreased for Long press as threshold pressure is increased. In the additional analysis, it was shown that 3D touch is failed because user did not press up to threshold pressure for 3D touch and Long press is failed because user pressed over the threshold pressure for 3D touch within threshold time(800msec) for Long press. Conclusion: Optimal threshold pressure has to be found for usability because error rate of both 3D touch and Long press is highly depends on threshold pressure for 3D Touch. Application: This result is expected to be applied for further research that identifying both optimal threshold pressure and user friendly threshold pressure.