Originally Posted by
TWA884
Google maps, when offline maps are downloaded and saved on the device,
Galileo Offline Maps and
Flyover Country. I'm sure that there are more apps that are capable of showing your position when not connected to data or WiFi.
On a recent flight from SFO to SAN Google Maps did display a map (and used GPS for location) despite flying over areas without offline maps. I suspect there's a low detail world map for such situations regardless of whether you choose to download additional ones.