Whistle is a clip-on tracker you can buy for your pet, that connects to an app on your phone via WiFi. You can set the app to recognize when the Whistle (and your dog) is in the “home” wifi zone, and the app will notify you when your dog leaves the house and track the location of your dog. This device is incredibly useful, especially for families like mine whose dogs have a tendency to wander. However, the app is also really fun! The Whistle functions not only as a tracker, but also as a sort of Fitbit, where users can see how much exercise their dog got, how long they rested, and even how much they played or chewed on a bone. I love this product because it is not only useful, but it also teaches users more about their dogs, and entertains and engages them. The product is not just practical, but pleasurable too.