What is the primary visual distraction when using a smartphone while driving?

The primary visual distraction when using a smartphone while driving is glancing at the screen. This type of distraction takes the driver's attention away from the road, impairing their ability to monitor traffic conditions and react to hazards. By looking at the smartphone screen, the driver must shift their focus, which can lead to a delayed reaction time to any unexpected events on the road. This is particularly dangerous since driving requires continuous visual and cognitive engagement with the surroundings.

In contrast, listening to a podcast involves auditory engagement rather than visual distraction, which does not divert the driver's eyes from the road. Looking around the environment may be a necessary part of driving, as it allows the driver to stay aware of their surroundings. Adjusting the rearview mirror, while it can be a distraction, does not typically involve the same level of visual commitment as focusing on a smartphone screen. Therefore, glancing at the screen stands out as the most significant visual distraction while driving.