Road warriors: Smartphones with built-in GPS

We already know that smartphones are...well, smart. They make calls, send and receive e-mail, surf the Web, play music and video, act as document viewers--a true Swiss Army Knife for mobile professionals. Now, we're starting to see another useful tool being added to smartphones--built-in GPS. Though the number of thusly equipped models is still small, the idea is catching on among cell phone manufacturers and service providers, as evidenced by the launch of several carrier-specific location-based services such as Verizon's VZ Navigator, Sprint Navigation, and AT&T's TeleNav GPS Navigator. Sure, you may thinking, "Great, just another feature being added for the heck of it," but we think the ability to turn your phone (something you'll probably always have with you) into a handheld navigator is something useful, rather than an extra luxury. With the embedded GPS receiver and a mapping service, you can get real-time position tracking, text- and voice-guided directions, and points of interest. Plus, the PIM tools can help you keep your schedule on track. Of course, there are trade-offs. The small screens don't make them ideal for in-car use, and the GPS radio will have an effect on battery life, but the voice prompts and always having your car charger can help alleviate those problems. Here are six smartphones with built-in GPS, including the new Apple iPhone 3G--and if none of these suit you or if you have a Bluetooth-enabled smartphone, remember you always can add this functionality with a Bluetooth GPS receiver.