It shouldn't be too hard to modify the .reg file to make this a little more specific, instead of just showing the state.
ie. 415 isn't the entire state of California, it's mainly just San Francisco & Marin Counties. (see
http://www.bennetyee.org/ucsd-pages/area.html or several other lists)
My question is, how will this app handle all the extra text? Would it be hard to modify the app to show both the state and area descriptions on separate lines?