A study of young adults examining phone dialing while driving using a touchscreen vs. a button style flip-phone

• In a simulator, we evaluated the effects of phone dialing while driving.
• 36 young adults used both a flip-phone with tactile pushbuttons and an iPhone.
• Glances to device (long duration in particular) were more frequent with the iPhone.
• Non-touchscreen users slowed down when they were dialing with either phone type.
• Touchscreen users slowed down only when they were dialing on the flip phone.

A simulation study compared 36 young adult drivers’ eye movements, driving behavior, and task completion time while dialing a flip-phone with tactile pushbuttons and an iPhone which provides a touchscreen interface. Once recruited, information on experience with different phone types was collected from each participant, which was then used as a covariate in statistical analysis. Participants who often use a traditional manual button phone completed the dialing task faster when using the flip-phone compared to touchscreen users using the iPhone. The flip phone, in general, resulted in fewer glances to the device than the iPhone. The mean number of glances greater than 1.6 s with the iPhone was 2.1 times the mean number with the flip phone. Further, females using the flip phone had the highest percentage of time spent with eyes on the road and the lowest likelihood of exhibiting long duration off-road glances (i.e., greater than 1.6 s and greater than 2 s). In terms of driving behavior, non-touchscreen users were found to slow down both when they were dialing on the flip phone and the iPhone, whereas touchscreen users slowed down only when they were dialing on the flip phone. Standard deviation of lane position was the highest when not dialing a phone, followed by when dialing the flip phone, and was the lowest when dialing the iPhone. Advantages appear to exist in a traditional tactile manual interface in terms of allocation of visual attention and possibly in compensatory behavior.