Apr extension is related to ArcView project file. You can run apr files with Archview software.
ArcView : It stands for geographic information system (GIS). Gis system is a map visualization and analysis software. You can open apr files with Arcview software. If you wish you can download arcview software from www.esri.com
Besides you have chance to get detailed information from this web page.
What to use APR
which page related to APR file
APR Related Searches
You can check related links about APR fileextension.