Looks like you need to count on another user to have the app running on their phone when they happen to be within 100 feet of your luggage with the app running. which will give you a one-moment-in-time view of where your luggage is/was.

Sounds like a bit of a longshot unless they get a seriously critical mass of users. Perhaps $25 is worth the low probability, but given that I've never lost a bag in 25 years of travel, I won't be buying.