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Display
Look for color displays
that are easy to see in all
lighting conditions,
such as the one found on
the Magellan Maestro 4370.

Select a GPS model with a good color screen that can be read in all lighting conditions. The larger the screen, the more expensive the unit will be, but even big screens can be difficult to read in direct sunlight. Also, check the viewing performance of the display to make sure you can read it from any angle.

Maps
Look for a model that includes street-level maps for the areas you frequent. Most units sold in the U.S. market feature built-in maps for the lower 48 states, but if you often find yourself in Alaska, Canada, Hawaii, Puerto Rico, or Mexico, make sure that your chosen device includes the appropriate maps. If you want to use your device on an out-of-country vacation, most manufacturers offer add-on maps, for an additional cost, that expand your device’s usable range.

For OEM systems, this often takes the form of a replacement DVD. For PNDs and installed systems, the maps are either shipped on flash memory cards (SD, microSD) or downloaded and synced via USB.
Design

GPS devices come in all
different shapes and sizes.

The first choice you’ll have to make when selecting a car GPS device is design. For example, a user with a used car will have to decide between the simplicity and inter-vehicular portability of a PND and a clean-fitting, feature-packed installed system. Choose a GPS unit to fit your traveling habits.

Users buying new vehicles have the third option of selecting a vehicle equipped with an OEM system. For OEM systems, there’s often very little choice, as most manufacturers only offer one navigation system per vehicle. However, there are a few cases where you’ll have options. For example, the Mini Cooper can be had with a fully integrated in-dash system or with removable Garmin-based system. Users who want vehicle-to-vehicle portability should probably choose the latter.

In the world of portable navigation devices, there is considerably more freedom. Users have a vast array of screen sizes and aspect ratios available. From the pocket-friendly 3.5-inch TomTom Ease to the massive 7-inch Magellan Roadmate 1700, there’s a GPS design to fit most users’ size, feature, and budgetary requirements.
Navigation features
Like anything else, the more bells and whistles included in your GPS system, the more you’ll end up paying, but there are certain features that are more or less standard equipment these days. Street-level maps with voice- and text-prompted driving directions are the foundation of any in-car GPS system worth it’s salt, and we’re starting to see more and more systems that use text-to-speech technology to deliver specific street names rather than more-generic instructions, such as, “Turn right in 0.5 miles.” A comprehensive POI database containing airports, hospitals, dining, shopping, service stations, and more, is a must if you’re traveling in unfamiliar territory, as is automatic routing from a POI, an address book, or your present location. Look for a device with touch-screen controls, automatic rerouting when you veer off course, and variable map views, such as 3D and bird’s-eye views. As you get into the high-end models, look for advanced lane guidance, voice commands, and real-time traffic and weather alerts, which usually require an annual subscription fee.
Accessories

Most companies include
the basic accessories like
vehicle mounts and car chargers
in the box.

Most in-car navigation systems are ready to use right out of the box and come with everything you need to get up and running in a matter of minutes. Still, there are accessories available that will help you get the most out of your investment, including auxiliary antennas that can be mounted at the base of your windshield to improve signal reception, and carrying cases to protect your GPS unit when not in use. You can also pick up various mounting devices, including removable dashboard mounts, motorcycle mounting kits, and low-profile external antenna mounts that adhere to the trunk of your car. You can also purchase additional maps via download or flash memory cards, as well as AC adapters that let you use your GPS unit at home.

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