Apple iPhone 3GS
When it comes to lifestyle functionality, most tech reviewers maintain you can't do much better than the Apple iPhone. With a great GPS built in and every PDA capability you could imagine (including access to an applications store that allows for the download of even the most obscure PDA capability), it's the iPhone that has become a must for consumers looking to stay on course, both literally and figuratively.
The Palm Pre
The newest standout in the smartphone sphere. This multi-touch smartphone offers great PDA capabilities with a wonderful GPS integration. Wi-Fi and Bluetooth are integrated, and simultaneously running apps make this a great multi-tasker. Unfortunately, the battery life leaves a lot to be desired, and the App store is not yet fully developed.
RIM Blackberry Curve 8900
The sleekest Blackberry on the market offers a more solid construction, the best PDA capabilities for professionals, and solid GPS capabilities. But since it doesn't have 3G support, it can be a little sluggish if you're not in a Wi-Fi hotspot. This is by far the best offering for smartphone users from T-Mobile.
Nokia N810 Internet Tablet
If you've got a phone that you love, but still want PDA capabilities melded with GPS technology, the Nokia N810 Internet Tablet is a solid option. It's a sleek interface and design, with a slide-out QWERTY keyboard. There's even Rhapsody and Skype support for music lovers and people in need of texting service. Driving directions cost extra.
Mio DigiWalker P550
Another solid option for those longing for PDA and GPS tech, but no phone capabilities. Bluetooth and Wi-Fi are built in, as are maps of North America, and three years of a WorldMate travel app. The battery life and directions, however, leave a little to be desired.