There's really no way to do that. If the map isn't shared, the app can't be either. Or if the app were loaded, it would immediately hit an error when it tries to load the configuration of the map, and that file is inaccessible to the user.
Unless the map is shared with a group that has shared updating enabled, nobody else will be able to update your map, so that's not really an issue. Are there things in the map that are somehow sensitive?
- Josh Carlson
Kendall County GIS