I found a lost iPhone at the drug store the other day. I heard a phone ring, realized it wasn't mine, and looked under a brochure on the counter and found the phone. It had the owner's photo as wallpaper and the pharmacist recognized her. So she'll get her phone back.

Most phones have access to info the owner provides via the lock screen, usually emergency and health info, but it's not always intuitive to find. And iPhones tend to be fairly secure if the owner sets up a proper password and enables the option to wipe the phone after too many incorrect password entries. But I've noticed some folks don't bother with any kind of security -- no pin, no thumbprint activation or anything. Bad idea, especially for folks who stay logged into Google, Facebook, Amazon and other accounts that may also be linked to purchasing options.

Seen this a few times lately on TV shows. Seems to be one of those things that gets passed around occasionally. I've never done it on my phone but my Garmin has contact info on the startup screen.

I've got a 3 year old Samsung and it has "find my mobile" installed in it and you can also get this from Google. Your phone simply needs a GPS in it which most have these days. You simply get on your home computer, log in and it shows on a map where your phone is. Google also offers this which I've also tried. With Google, you can not only locate your phone, you can also remotely lock your phone so no one can use it, have your phone ring in case you know it's at home somewhere and even erase your device. I've tried this (locating the phone) at home and sure enough it showed my phone on a map being at my address. I also have tried having it simply ring and that worked too (actually I really couldn't find my phone at home, it was in the garage!)
Edited to say that, of course all of the above only works if the battery hasn't died on your phone.

I need a t-shirt that sez that.