GPSy -- Macintosh GPS Communications. GPSy is the only Macintosh GPS program compatible with
any NMEA-0183 compatible GPS/Loran-C/DECCA or other navigational system.
Chimoosoft's GPS Connect for Mac OS X is a freeware program which connects to Garmin GPS receivers and allows upload and download of waypoints. NMEA Protocol is also supported for other brands of GPS receivers.