I have it on my keys and in my wallet, and it has proven very useful over the past months. After you search the entire closet for keys, you open the app and see that you put them into your bag across the room. And when you panic that your wallet is not inside, you check and see the last location is at your office so it is probably still waiting you on your desk.
So if you misplace your things from time to time this is a thing for you. It might save you some unwanted stress and time when something gets lost again.