Previously download custom terrain

Any terrain data that gets downloaded will stay with the app for use while off-line. The best thing to do is design a preliminary flight plan while you are connected to the Internet and check the terrain profile using the terrain data source you want to use. Everything will be downloaded at that point. You could also design the flight and hit the suitcase icon in the Mission Plans screen to pack up everything you need to be able to go off-line. Only the terrain data sources you view the profile for will be saved. When using the pack and go button iit will use your most recently used terrain data source.