There is only one file type that uses the .NM2 extension:
Navitel Map File
Map file used by Navitel navigation software; contains a map of a specific area, including roads, landmarks, GPS coordinates, and other map data.
NM2 files can be loaded by Navitel software, which is available for Android, iOS, Windows Phone, and Symbian devices. They typically have file names that describe the location of the map, e.g., North Central Croatia.nm2.
Updated: February 23, 2013