I travel not only around the United States, but internationally as well. This app was a lifesaver for me. You can download detailed maps of the city, and customize what kinds of places show up on the map (restaurants, bars, shopping, museums, etc). Once the city map is downloaded, you obviously do not need to worry about a wifi signal or being in a network. In addition, the GPS will show you where you are on the map and update continuously as you walk. I was able to wander the streets of Sevilla without any cell phone service, yet always know where I was and never get list thanks to this app. Absolutely essential for the traveler.