It works just like the web version of the Android Device Manager (http://goo.gl/QzXm0G): you can see any device associated with your Google Account, ring to locate those devices, or protect the information stored inside by remotely adding a screen lock or performing a factory reset to erase your content. The app is particularly useful if you’re out and about and don’t have access to a computer.
It’s one app we hope you never have to use, but at least now you have the peace of mind if you find yourself in a bind.
Be sure to check out these tips for keeping your Android phone or tablet safe and secure: http://goo.gl/wv5g18