Many apps automatically change from portrait to landscape mode as you rotate the device in your hand. We found in practical use when outdoors or in a moving vehicle, this becomes annoying as it frequently happens by accident.
However it is easy to switch the orientation of the app. Simply tap the Back button to close the app, rotate the device into the desired orientation, then relaunch the app. (Note that closing the app with the Home button does not achieve this, you have to use the Back button).
The map display orientation is fixed in Memory-Map. There is no course-up or heading-up mode.
Next: Using Online Maps