You've seen this person. Maybe you've even been this person.
We're talking about someone shuffling along a sidewalk or through a shopping mall, so entranced by the phone in their hands that they bump into people or almost get run over.
Yes, this behavior can be annoying. Now we have scientific evidence it can be dangerous. A new study has found that people who type or read on their phones while walking are less likely to look at their surroundings, keep their balance or walk in a straight line.