PitPat GPS ('the big one') is our flagship dog tracker, and can locate your dog in two taps from the PitPat app. It also includes all the features you get in the PitPat Dog Activity Monitor, so you don't need both devices.
The PitPat Dog Activity Monitor ('the little one') doesn't have GPS, and can't be used to track your dog's location. Even so, it's loved by hundreds of thousands of pet parents for the award-winning activity monitoring, that allows you to see exactly how much exercise, rest and play your dog is getting.