From the March 2008 issue of Entrepreneur

There's no excuse for getting lost or being late anymore. You can subscribe to GPS services on your cell phone or even pick up one of the popular standalone GPS units for your car--or your pocket. Check with your cell provider to see if it offers a subscription service like VZ Navigator from Verizon Wireless. That particular service costs $9.99 per month or $2.99 per day. It can be a good deal for infrequent GPS users or for entrepreneurs who don't want to carry an extra device.

Text-to-speech is one of the most sought-after features for a GPS unit. Instead of hearing "Turn right in 100 yards," you'll hear, "Turn right at MacArthur Blvd." Most low-cost units don't include this feature, but the $249 entry-level Navigon 2100 is one exception. For $100, you can add a subscription-free traffic alerts package that's good for as long as you own the unit.

Another entry-level device to look into is the $250 Mio Digiwalker C230. It comes stocked with text-to-speech, and at just over 5.8 ounces, you can easily carry it along with you when you're not in your car. It's an inexpensive option for a solid starter GPS. The pocket-friendly Magellan RoadMate 1200 costs even less at $230, but you won't get text-to-speech. Its no-frills design will appeal to GPS beginners who are looking for an uncluttered navigation solution.

TomTom's popular One line features a collection of entry-level and midlevel GPS units. The $400 TomTom One XL.S includes a spacious 4.3-inch touchscreen, text-to-speech and Bluetooth in a 6.5-ounce package. Its maps are easily updated through the TomTom Home service and the Map Share community. The "Help Me!" menu acts as an emergency guide to help find the closest hospital, police station or car repair facility. The One XL.S also gives you the option of adding real-time traffic information by tethering a compatible Bluetooth mobile phone to the device. Just be aware that you may incur service provider data charges.

When it comes to fully loaded GPS devices, the Garmin Nüvi 770 packs in the goodies. The $900 price is on the high end of the spectrum, but you get an FM transmitter to send audio through your car stereo, Bluetooth compatibility for your phone, a picture viewer, calculator, currency converter, Garmin's Lock theft prevention system, an integrated FM traffic receiver and a world clock. Besides U.S., Canada and Puerto Rico maps, you also get maps of Europe. Entrepreneurs who travel internationally can make good use of these added features.

Depending on which vehicle you have (or plan on purchasing), you may not need a standalone or cell phone GPS solution at all. GM's OnStar (onstar.com) provides turn-by-turn navigation for $28.90 per month or $299 per year for vehicles that are model year 2007 and newer. Some 2008 Chrysler models have the in-dash MyGIG infotainment system with 6.5-inch display and GPS navigation as an available option.

With falling prices and an impressive range of features, portable GPS units should stay at the top of many entrepreneurs' must-have gadgets lists.