Where does the RealAR work?

Almost anywhere, as long as the app can detect a flat surface where a model can be rendered.

To experience inside of a building, the 'dolls house' view is great for 360 degree perspectives. It allows you to experience a model from the inside as if it were a real building. 

For outside, models can be experienced in any open site, life-size, in first-person, as if you were standing outside of the real building.  Since the camera is used in this app it works best in well lit areas.