[downandout]

Maybe tie the the back end into repossession company databases. Have the user turn it on when in parking lots and they get a commission when found. A local repo service is instantly alerted with GPS coordinates whenever there is a hit. The app could even alert them to stop and observe until the repo company gets there.

Certainly not a mass consumer thing, just like most people won't become Uber drivers, but some people would do it and there is potential for making decent money.