It's best used for hiding goodies that the kids might otherwise find, but it's also good for hiding a phone in a place you can't readily access it. (cnet.com)
There were hidden goodies in the levels I played as well. (gimmegimmegames.com)
You can hide goodies inside rubber cubes called busy - box toys, and your dog will try to find them inside the cubes. (4mdogbooks.com)