GPS software extends the capabilities and usefulness of any GPS device. And once you know what your needs are, you'll find you aren't limited to only your GPS maker's software. The land and water coverage for anywhere in the United States is extensive and can make trip planning easy.

Basemaps
A common feature of GPS mapping devices is the basemap. It's permanently installed in the GPS unit's memory by the manufacturer. The map typically covers the major roads and geography of a country. While these maps are fine for cross-country travel, they're not detailed enough for travel around town or on the water.

Electronic GPS Maps
Whether you're flying, driving, boating or simply walking, there's a GPS electronic map to get you where you want to go. Detailed maps can be downloaded from a CD or the Internet and stored in GPS units with available internal memory or on removable memory cards. GPS manufacturers use proprietary map formatting, so their maps won't work with other brands. But there are some third-party software creators whose maps will work for a number of GPS models.

GPS Map Software
The Garmin company makes a wide range of GPS map software to work with its receivers. There are detailed color maps designed for navigating cities, water recreation areas, the backwoods, or for flying. Using Garmin's MapSource software, you can view maps on your computer, plan your trip and edit your waypoints and routes. Prepared maps can then be transferred to a GPS device with an interface cable connected to the computer.

Like Garmin, Magellan not only makes popular GPS units, but the GPS map software to go along with them. Street-level maps let you use autorouting to quickly find city destinations. And the level of map detail is controllable, so you can eliminate unnecessary clutter. If you want maps for hiking, there are 3-D topographical maps available. Along with the natural land features, the maps include man-made structures such as dams, towers and wells.

Street Atlas is Delorme's flagship product for GPS map software. It's designed to work with its Earthmate receiver as well as most other companies' GPS units. The software combines both private and public data sources to position and identify over 6 million streets and 4 million points of interest in the U. S. It can automatically route a trip, even coast to coast, using the shortest distance or the quickest time. With the software running in a laptop connected to a GPS device, you can also get real-time guidance. The program accepts voice commands and will respond to questions like, "How far to the next rest stop?" The maps can be marked up to include notes or special symbols.

Marine GPS Software
Although Lowrance has maps for both land or water like Garmin and Magellan, they excel with their marine GPS software. The maps cover lakes, rivers, and tributaries along with extensive navigation aids, obstructions, and wrecks. The fishing maps feature depth contours and soundings, plus the hot spots for fish. A searchable database lets you find marinas or lodging as well as points of interest. Lowrance uses memory cards, either preloaded with a map or a blank to accept your custom created map.

Aviation GPS Software
For traveling through cities, TeleType has GPS navigation software with the usual software features. But for the flyer, their software really shines. You can either use their GPS receiver or another maker's if it's NMEA compliant and has a serial connection or is Bluetooth enabled. The software lets you plan your flight with its FAA database of airports and related information. Then its real-time moving map display guides you to your destination airport. Along the way you might use the closest airport display, or check the altitude relief maps and elevation grids, or get the up to date NEXAR weather images. When ready to land, you'll find full runway information including taxiway maps.

GPS Navigation Software
GPS navigation software isn't limited to the makers of GPS equipment. Companies like MapTech can also help guide you on land, water, or in the air. Their topographic maps are based on U. S. Geological Survey (USGS) maps and cover the entire United States. You can view the maps in either two or three dimensions, or both using a split screen. The display options let you see the terrain from any angle and under a variety of conditions, such as daylight, fog, or moonlight. Besides standard trip editing features, the software lets you view terrain profiles and create elevation graphs.

Navigation software for PDAs users, both Palm and Pocket PC types, is available from Mapopolis. You can download their Navigator software and a demo map to test it out. It can operate with your PDA wired to the GPS receiver or wireless if both are Bluetooth enabled. The software can provide guidance in real time and among other features, it offers voice prompts for turns and automatic rerouting if you get off track.

GPS Mapping Software
For versatile GPS mapping software, look to independent software companies like Fugawi. Their software lets you create digital maps from scanned paper maps or a map database like those for government topographic maps. Their software can import a variety of map formats and they also sell maps on CDs. As with other electronic maps, you're free to edit waypoints and routes on your computer, then upload them to your GPS receiver. And if you run the software on a PDA you can have a real-time map that moves as you do.

If you're especially interested in printing maps, a good choice for software would be ChartTiff's. Their mapping software lets you print maps in a range of sizes, scales, and grids using either their data or your own. They also offer both standard and custom digital maps as well as the paper type.