Mind you don’t walk into anything when you’re dumbwalking.

dumbwalk

/ ˈdʌmwɔk / verb

to walk along without looking where you are going while using your phone:
I just saw two people dumbwalk into each other.

A person who is walking like this is called a dumbwalker:
Dumbwalkers are taking their life into their hands when they cross the road.

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