GeoMap is a robust Google Map GPS application with over 6000 locations of Speed Cameras, Red Light Cameras and Petrol Stations in Australia.
It is way better than the default iPhone Map Application because you can change in-between Standard, Satellite and Hybrid views of the map.
You can also pin-down your current location on the map with a click and see your current GPS coordinates.
(Note: The first-run of the application will require longer time to install the GPS POI coordinates database into your iPhone. After the first-run this application will run very quickly to track your GPS position, and get the closest Speed Cameras and Petrol Stations around you.)