Agent Derek Meister-Geek Squad spoke to Bill about It's a Good Idea to Download Google Maps Offline. Here's How to Do It. Your mobile phone and the Google Maps app have replaced standalone GPS units for many car owners. But on a long car trip, you might encounter an area with little to no cell signal. And that means your Google Maps app can stop functioning. Fortunately, the fix is to download an offline map of any big trip you're taking as a precaution.