GPS mapping software has long been in a Windows-only world, but some helpful software has recently been developed for Mac.

Consumer Level

Maptech Terrain Navigator Pro ($300 or less with California maps), Windows

National Geographic Topo ($50 or less with California maps), Mac/Windows

ExpertGPS ($75, mapservers), Windows

MacGPS Pro ($60, mapservers), Mac

Google Earth (free), Mac/Windows

Garmin Basecamp (free, no maps; $100 or less for California map), Mac/Windows

Professional Level

ESRI ArcGIS ($1500 to unlimited), Windows

Quantum GIS (free) Mac/Windows/Linus