Whistle GPS Pet TrackerNew Find lost pets quickly Whistle GPS notifies you if your pet ever roams from their Whistle zone, a customizable safe area you designate for your home or office, and allows you to track their location directly from your smartphone. Nationwide coverage Whistle uses cellular and GPS technology to track your dog's location anywhere you get cell service in the U. S. On demand alerts receive notifications via app and text alerts when your pet gets out