What the best car GPS has

  • Quick, accurate navigation. Fancy features won't help you get where you are going if your car GPS system can't give you the right directions (and yes, some auto GPS units struggle with this basic task in tests).
  • Easy-to-use maps and menus. Complicated GPS systems are not only frustrating -- they can be downright dangerous to fiddle with while you're driving. The best car GPS navigators are easy and intuitive to use.
  • Spoken directions. Car GPS systems should at least announce street names (e.g., "Turn left on Elm Street in 100 feet" instead of just "Turn left in 100 feet"). Nowadays, better auto GPS units -- even the cheap ones -- can give you landmarks (e.g., "Make a hard left at the Honda dealership").
  • A touch screen. Budget models are tap-only, but some upscale GPS navigators let you pinch, zoom and swipe the display.
  • Lane assist. Even the cheapest auto GPS navigators will guide you into the proper lane at an interchange, showing you a realistic view of the actual road signs you need to follow.
  • Millions of preloaded points of interest (POIs). The best auto GPS units also let you add your own custom POIs.
  • A windshield mount. Basic car GPS models come with a suction-cup windshield mount, and some also have a dashboard mounting disk.
  • A vehicle power cord. With most car GPS systems, you'll plug the cord directly into the navigator itself. Some let you plug the cord into the mount, making it easier to take the navigator in and out of the car.

Know before you go

How big should you go? For years, 4.3-inch GPS screens were the standard. Now, most car GPS systems have 5-inch screens that are easier to read at a glance. Bigger 6- and 7-inch screens are available, but experts say these can block a sizable chunk of the windshield; they're best suited to very large vehicles like full-size pickups.

Voice commands can make navigation safer. This is one frill that's really helpful. Upper-tier car GPS systems work by voice commands, so you won't have to take your hands off the wheel.

What maps do you need? Basic car GPS systems come with preloaded maps of the United States. Step-up models add maps of Canada, and they usually don't cost much more -- but the model numbers are always similar, so double-check that you're getting the right maps.

Are map updates included? It's smart to buy a car GPS system that includes free map updates for the life of the unit, experts say. It'll add maybe $20 to the price -- but a map update costs $60 to $80 otherwise.

Do you need traffic alerts? Free traffic alerts usually cost just a little extra on budget navigators (high-end units automatically include them). These work well in tests, steering users clear of traffic jams -- but only on major highways. On city streets (even in major cities like New York) and side roads, GPS systems usually have little traffic information. If you don't drive in well-covered areas -- or you rely on a smartphone app like Waze or Google Maps for your traffic info, which some owners say works better, you may be able to skip this feature.

Could you just navigate with your smartphone? Free smartphone apps like Google Maps can do nearly everything a standalone car GPS system can do -- and did we mention they're free? However, dedicated auto GPS units can be easier to use, easier to see, and they won't drain your phone's battery or eat up your data plan. See the discussion in Car GPS Reviews for more car GPS vs. smartphone pros and cons.