[kbanman]

The article doesn't dive into why this group performed worse; to me that is of much more interest than the conclusion.

Just from my own observations I would expect that this is largely due to income differences in the two groups. Rich people are more likely to own iPhones and in my experience also more likely to be careless drivers.

[okwubodu]

I think iPhone users skewing younger is likely to be the culprit.