Turn Your Smartphone Into a GPS Navigation System with Garmin Mobile XT

Capitalizing on the growing number of smartphones equipped with GPS, Garmin has introduced the Mobile XT: a complete navigation system contained on a microSD card. Just pop it into your phone to turn it into a full-featured GPS, complete with moving maps, turn-by-turn directions, automatic route-recalculation, and millions of points of interest.

The Mobile XT also leverages your phone's wireless capabilities to fetch real-time traffic alerts, gas and hotel prices, and weather forecasts, but without the added fees you usually have to pay for that kind of premium content. Garmin's cool-sounding PeerPoints feature enables you to send your position to any other phone and navigate to the location of other Mobile XT users.

If you've got $99 to spare, the Mobile XT can be yours. Just one wrinkle: At the moment it's compatible with just four smartphones, those that have GPS chips powerful enough to handle this kind of navigation. Those phones are the HP iPAQ 6510, HTC TyTN II, Moto Q, and Nokia N95. Don't have a compatible smartphone? Try the $199 Garmin Mobile 10, which offers the same GPS-on-a-memory-card features but adds a Bluetooth GPS receiver to the mix. It's compatible with a much broader range of models.

If you do decide to use your phone for in-car navigation, make sure to get a dashboard or windshield mount that keeps it close to eye level. (Leaving it in your lap or on the seat next to you is really, really unsafe.) I've long been a fan of ProClip mounts, but a Google search will reveal plenty of inexpensive and effective options.