HP has concentrated more on traditional PDAs than smartphone PDAs in recent years, but their new Voice Messenger series shows that they're ready to get their feet wet with the latter. The iPaq 510 Voice Messenger offers a variety of voice-enabled features that give you hands-free control of this PDA.

For example, you can use the voice commands to open applications or play music files, and the 510 will read your appointments back to you. You can even respond to e-mails without having to type by using the VoiceReply feature that sends a recorded response to your recipient. The phone supports voice over IP (VoIP) for making phone calls over the Internet, and it wouldn't be worthy of the name Voice Messenger if it didn't let you record voice memos as well.

This smartphone PDA is running the latest Windows Mobile 6, so you've got access to mobile versions of Word, Excel, PowerPoint, and Outlook in the shiny new Vista-like interface. There's also a 1.3-megapixel digital camera that snaps photos and can e-mail them to your friends. There's no flash, so it's mostly for daytime or indoor use, but the camera records respectable video clips.

The iPaq 510 gives you a variety of ways to stay connected. It's a quad-band GSM/GPRS/EDGE cell phone so you can use the cellular network to browse the Web and stay in communications wherever you have a cell signal--including internationally. It offers 802.11b/g wireless, letting you get online via your favorite WiFi hotspots. And the Bluetooth 1.2 technology synchs up wirelessly with compatible PCs as well as utilizing Bluetooth peripherals such as headsets and printers.

But one of the best features of this smartphone PDA is its size. Weighing in at a little more than three and a half ounces, it's one of the more portable PDAs we've ever seen. Of course, this compact frame also directly limits the screen size. The two-inch screen offers sharp 220x176 resolution, but it's one of the smallest PDA screens we've ever seen.

The iPaq 510 is running a 200MHz TI processor, though it seemed to open files and applications quickly. There's 128MB of flash ROM for storing MP3s and other files, and HP also included a microSD slot to expand the storage room of this smartphone PDA.

The iPaq 510 is one of the better buys on a smartphone PDA front and earns it our Budget Buy rating, although you don't get any price cut for signing a service contract with most providers. Battery life gives you 6-1/2 hours of talk time with over a week of standby power.

If you're looking for a very compact smartphone PDA that really relies on voice commands to get things done, the HP iPaq 510 Voice Commander is a well-designed cell phone/PDA for an excellent price.

Pros: Very compact, excellent voice capabilities
Cons: Small screen

Warranty
90 days, software support; 1 year, limited