Dorothy Gale had it easy—she needed only to follow the yellow brick road to find her way to the Emerald City. Now, thanks to the increasing affordability of Global Positioning System (GPS) devices, we have it just as easy if not easier. With features like turn-by-turn directions and voice prompts, finding your way to and from your destination is akin to clicking your heels three times. Developed by the US Department of Defense for military tactics, GPS technology is a 24/7 radio navigation system that identifies and tracks the location of the GPS device virtually anytime, anywhere.
GPS devices get their data from 24 satellites orbiting Earth. Locking into a minimum of three satellites determines your location in longitude and latitude. Some devices routinely lock into four satellites to provide altitude. Use of the satellite network is free—all you need is an unobstructed view of the sky, but while GPS devices will work under cloud cover and inside cars, they may falter under heavy tree canopies, inside tall buildings or tunnels, or dense urban areas with lots of skyscrapers.
Pronto’s Auto GPS Buying Guide will help you select the GPS device that meets your needs (see also Handheld GPS Buying Guide).
Will you need it only for your primary vehicle or do you want the flexibility to bring it with you? How often and for what purpose(s) you’ll use your GPS device will determine which option is best for you.
Look for easy-to-read displays with easy-to-navigate menus. If your device is hard to read or awkward to use, chances are you might not use it at all.
Determining how much you need your GPS to do will help narrow down which model is best for you. Do you want your device to be able to store and run other media applications?
If alternate routes around traffic or construction is a must, consider a device with a traffic receiver or purchase a separate traffic receiver (traffic data is available by paid subscription).
Nice to have if you’re willing to pay for them: voice-to-text which includes street names in the audio transmission or Bluetooth capabilities that allow you to call a hotel, restaurant or other destination and keep your hands on the wheel.
Provide general coverage of cities, towns, highways and bodies of water. Most units come equipped with built-in basemaps, but units without mapping are also available. Manufacturers may also offer basemapping software that allow you to upload new or different basemaps to the device.
Specific map locations, such as ATMs, gas stations, restaurants, etc. If having access to these locations is important to you, you’ll want to look for devices that can connect to your computer for geo-targeted data downloads.
Specific locations delivered in latitude and longitude. The more waypoints your device can store, the more accurate its navigation output. Standard GPS devices come within 10-15 meters. If you need more accuracy, look for GPS devices that support Wide Area Augmentation Systems (WAAS) or Differential GPS, both of which increase accuracy to within 3 meters.
Time to First Fix or the time the receiver takes to find its position in a new location. The SiRF Star III GPS receiver is the de facto standard for GPS devices because of its fast TTFF and its ability to acquire/maintain a signal in denser and more urban environments.
Where and how you’ll be using your Auto GPS device will determine which one is best for you. Auto GPS devices can be installed in your vehicle’s dash for permanent placement or mounted on your dashboard if you’ll be using it in multiple vehicles. While in-dash models require professional installation, keep in mind that some mounts for portables do too. When choosing a portable mount GPS device, be sure the mount kit is compatible with your vehicle’s specifications.
Auto GPS Device displays are typically 3.5 to 5 inches (devices designed for RVs may be as large at 7 inches) and can come in color or monochrome. Color will cost you more, but if makes reading the screen easier, especially at a glance, it’s worth the investment. Above all, you want your device’s display to be easy to read and offer easy-to-navigate menus. Your most frequently used functions should be no more than two (2) screen taps away and it should be no more than another two (2) screen taps to get back to the original screen. Better still are voice-activated devices that enable you to keep your hands on the wheel at all times.
Almost all GPS devices come with manufacturer-installed US street maps. Additional software is available if you need off road or international mapping capabilities. Look for device software that offers turn-by-turn directions and/or enables you to upload your own maps, Waypoints and Points of Interest (POI), especially if you drive long distances regularly and need to track rest areas, hotels, toll booths, etc. For maximum flexibility, consider devices that allow you to choose your destination point via maps, custom address books or manual data entry.
How much storage you choose depends on how frequently and extensively you travel and whether you prefer to upload your data with or without the aid of your computer. If you need to save map information for several areas, you’ll need space to store them (a single Metropolitan area takes approximately 8Mb of storage space). If you prefer not to upload your data to your computer, additional memory can be purchased in the form of Compact Flash (CF) or Secure Digital (SD) cards which can be swapped on the road or in the field as needed. If you prefer to store your data on CF or SD cards, you’ll need a GPS Device with the appropriate slot for data access.
Traffic receivers do more than just provide alternate routes during rush hour jams—they also track construction and/weather-related detours. Look for devices that include a traffic receiver or note which traffic receivers the device is compatible with if you don’t want to commit now, but might add it later. Traffic data is available via paid subscription, typically $50 per month.
GPS devices can also function as multimedia players that store and play music, audio books or even sync with satellite radio networks you subscribe to. If you want a device that does it all, be sure it’s able to play your other applications and still fulfill its primary function of navigation. Some units are only able to perform one function at a time. Other nice-to-have options include voice-to-text, whether computer-generated or celebrity-recorded, which delivers your driving prompts with street names included. Bluetooth compatibility helps keep you safe on the road by enabling you to place hands-free calls to destinations on the map (e.g., to check hotel vacancies).