New direction in GPS

Cell-phone GPS services can provide an alternate route to getting navigational help. They have most of the same core features and functions as dedicated GPS devices. But overall, cell-phone GPS services aren't quite as convenient.

We tested six cell phones with GPS capability: the Apple iPhone 3G, LG Scoop, LG Voyager, Samsung BlackJack II, Samsung Instinct, and T-Mobile G1 Google phone. The Apple and the Samsung Blackjack II used AT&T service; the LG Scoop, Alltel; the LG Voyager, Verizon; the Instinct, Sprint.

To activate the service, you generally download the software from the provider to the phone. Verizon uses VZ Navigator software; AT&T, Alltel, and Sprint use TeleNav. The price for using the service is usually about $10 per month or $3 for a single 24-hour period.

Exceptions are the Apple iPhone 3G and T-Mobile G1, which use Google Maps and GPS to provide navigation service. Google Maps shows your location and plots a route to your destination on the display. But the phones can't provide spoken turn-by-turn directions as a conventional GPS device does.

The other cell services work much like traditional GPS. Once you key in an address or choose a point of interest, the service calculates a route to your destination and provides turn-by-turn onscreen and spoken directions.

Bottom line

Our testing showed little performance difference among providers. But generally smaller screens and controls can make phones more difficult to use than dedicated GPS units. Phone navigation is an option if you don't want to carry another device, but if you're a heavy GPS user, you're probably better off with a low-cost portable device.

Learn more about cell-phone, portable, and handheld GPS units and see GPS Ratings.