So my father-in-law found an iPhone 5 in front of the house, screen smashed, but still able to power on. Even the touchscreen was still responsive!
Unfortunately, the owner engaged in the smart practice of locking their phone, so I can't troll through their personal information looking for a way to contact them (like their email address, a phone number called "home," or similar).
Then began a little odyssey in which I tried to reunite the phone with its owner.
Option 1: turn it over to the police
This is the easy and good-faith thing to do with a phone, but it's not that likely to get phone and owner reunited. For perfectly good reasons of better things to do, little time is spent on lost-phone cases. Even if the owner drops by the police station to try to find it, they may discover a large bucket of turned-in phones, and how to find theirs?
Option 2: turn it over to Apple