Maps And Navigation
The information your GPS receiver gets from the satellites gives it the location-the latitude and longitude of your current position, along with the altitude. It can calculate your speed and direction. Everything else comes from the navigation software and the map data on the device. So while your GPS will work in any country, you'll only get directions and points of interest if you buy the relevant maps. Check what's included in the price. HP's new iPAQ 5000 Travel Companion comes with a full set of maps for the country but the iPAQ Mobile Messenger and the standard version of the HTC P3300 only include one city map for the TomTom software they include. Some manufacturers offer free map updates to cover new construction, but most charge. You may be able to load a map into software on your PC to choose a custom area. A few GPS units have an internal hard drive, but most have flash memory and a memory card slot so you can add extra maps without having to connect it to your computer.
Basic maps have only main roads but most have a very detailed network of roads and locations. This is bought in from the large mapping companies. Both NavTeq and TeleAtlas produce comprehensive maps of most areas. Most GPS navigation software offers the choice of a map-like 2D view or a 3D view that looks more like what you see through the windscreen. The device will also give you spoken instructions, warning you of upcoming turns and how far away they are. You can usually choose from a number of voices (including John Cleese for CoPilot). Some newer units like the Magellan RoadMate 760 and the Garmin StreetPilot 2720 will speak the name of the road rather than just telling you to turn left or right.
The RoadMate 760 tells you what road to look for, not just which way to turn.
Simply choosing the fastest or shortest route doesn't always give you the best results. There might be, for example, a road near you that has major construction going on and you want to avoid a heavy-traffic zone. Simpler software like CoPilot lets you choose a single road to avoid at a time and gives you the choice of avoiding the congestion charge. TomTom offers a more powerful Find Alternate feature on models like the TomTom One, which lets you see more options and set an area to avoid. Look for a walking mode like the option on the Fujitsu Pocket LOOX if you're on foot ( after all pedestrians can go both ways down a one way street).
A planning mode will let you plan a route in advance, without having a GPS signal, so you can check the options out before you set off. Look for functions that calculate the details of trips you've already taken, like your average speed and how long you were stopped in traffic.
The easier it is to type in an address, the faster you'll be on the move.
Any GPS will let you tap in an address -though most on-screen keyboards are alphabetical rather than QWERTY. A combined GPS and PDA makes this rather faster and also means you can set a route to an address from your contacts book. Some, like CoPilot and TomTom, will direct you to the center of a town if you don't have a specific address. You can also choose locations from the Points of Information database, which is invaluable when you're looking for a restaurant, gas station or parking garage in an unfamiliar area. It can also be the fastest way to select your destination if it's a public place. Look for the option to add your own POIs so you can put friends' addresses, business contacts, speed camera locations or your own interests onto the device.
Look for a good database of Points of Interest that you can search in a flexible way.
Some dedicated GPS devices like the TomTom One have a Bluetooth connection so you can download traffic information via your mobile phone, which means your route can avoid jams automatically. If you're using a smart phone or PDA phone, CoPilot and TomTom offer this options and they can also send your location by email, so the people you're traveling to see know how far you've got.
Even when you know the route, use GPS to check the traffic for a faster journey.