Innocent people are commonly investigated because they were nearby when crimes were committed. Or because they somewhat match a victim's description of the attacker. Or because they're driving a vehicle that somewhat matches a description.

But this is taking it to another level. Here, location and time are the only identifiers. Once you've identified someone who was at the location of the crime when it was committed, they were either a perpetrator or a witness. Or maybe neither, because they weren't close enough in space and time.

But anyway, what happens next? Police hope to get a confession? Maybe some physical evidence. Or witnesses. But then, people often lie. And there's less opportunity for an alibi, except maybe a friend who says he was there with you. But his phone had better agree with yours.

And really, it's hard to imagine that someone doing serious crime would be carrying a smartphone. At least, one that's not turned off, and in a Faraday bag. But then, some criminals are just plain stupid, I guess.