From MP3Car.com Wiki
Because of its smaller user base, GPS software for the Macintosh lags behind its Windows counterparts. However, there are still several options for Mac users interested in GPS for the Mac.
- RouteBuddy: A GPS enabled mapping application for navigation, tracking and map analysis with proprietary map information. Now at version 2.1 with navigation and storage for large amounts of POIs and other geo-spatial data such as Geocaches. Worldwide road maps are available from North America and Europe as well as many other countries.
- Roadnav: An open source freeware mapping program. This program is most useful for U.S. users as it uses freely available road map data provided by the U.S. government (so-called Tiger/mapline data) for it's mapping database. A reasonably mature beta of the product is available.
- Google Earth: Using a companion program called GPS2GE, users can display their position on a moving map display in 3D with photo-realistic terrain data. Limited to the amount of data that the user can cache unless an always on internet connection is available.