This is a no frills app that does what it promises. I have misplaced my Fitbit several times, and every time it has located it ... inside shoes, inside the clothes hamper, inside jacket pockets, inside closets, under seat cushions. The premise is very simple: an arc spins on the screen when you're not nearby and starts to become solid as you get closer - the more of the arc that is solid, the closer you are. It's not complicated and it works. Sometimes ads pop up which become annoying, but only mildly so. Click the X and keep going or pay a small one-time fee and skip the ads. Caveat: It won't work with the device that it is synced with, so momentarily you will need to turn blue tooth off on that synced device while searching. For example, I have mine synced to my iPhone, so I turn off blue tooth on my phone and use Finder on my iPad. I guess if you only had one device and no partner or friend willing to download the free app, then it won't work. (Developers, if this caveat incorrect, please feel free to say so for other users.)