Photograph: Rick Rizner

It weighs a little less than five ounces and is only 4.5 inches long, but the H4150 has a lot of power and usability built in. You can have this Pocket PC's Bluetooth and Wi-Fi activated at the same time, and there are individual indicator lights for both on the top of the case, so you know at a glance which you've got running. You must turn the wireless capabilities on and off from a software screen, but the IPaq Wireless screen is easy to find and extremely easy to use because it contains just four buttons: Bluetooth, WLAN, All Wireless Features On, and All Wireless Features Off.

The H4150's 802.11b radio consistently recognized more of the wireless access points available in our building than did a Toshiba E800 we tested at the same time. For enterprise use, HP includes a LEAP registration utility, so you can log onto corporate 802.11x networks that require a user name and password. Other security-oriented software in this unit: a VPN client, an encryption utility, and an easy-to-use backup utility.

Besides the photo viewer that comes standard with the Windows Mobile OS, HP has included IPaq Image Zone, which lets you attach voice annotations to photos and make slide shows. The quickness with which the H4150 rotates and zooms in on large images shows that the 400-MHz XScale processor has muscle. Though the model doesn't have the highest-resolution PDA screen we've seen, photos and text had adequate detail and vivid color.

The small speaker on top of the H4150 is useful for system sounds only; music coming through it is thin and weak; audio piped through the headphone port is fine.

The H4150 comes with an extra stylus, an unusual and welcome touch. It would be nice if it also included a dummy card to keep dust out of the SD slot.

A getting-started poster is included with the H4150, but the manual is on CD only, and covers more than one IPaq line. It's well-written and well-organized, with adequate explanations, but it could use more illustrations. For example, there is no diagram of the various parts in the "getting acquainted" chapter. The on-screen Help system is context sensitive and pretty complete, so it's possible to work through most tasks without heading back to your PC to load up the manual.

Upshot: HP has created a powerful corporate PDA in a very compact package.

Rebecca Freed