Thinner, lighter, and as easy as possible to connect: That's the mantra Pocket PC vendors appear to be chanting--and trying to enforce--with mixed success on each new Wi-Fi-enabled handheld they produce. I looked at shipping units of three of the latest examples: two IPaqs from HP and a sturdy Dell Axim.

All three of these PDAs run Microsoft's Windows Mobile 2003 software for Pocket PC, and all three feature a 400-MHz Intel XScale CPU. Each has removable, rechargeable batteries and a charging cradle with a slot to accommodate a spare battery--a useful feature that Dell pioneered with its first Axim. All three handhelds have brilliant active-matrix touch-screen displays, as well as SD card slots for peripheral devices, memory, or data cards. Despite their similarities, however, the units differ significantly. HP's $449 IPaq H4150 is a mere 0.5-inch thick and has the rounded bottom and general look of two other recent thin-and-light IPaq models, the H1935 and the H1940. The second IPaq I tried, the $499 H4350, is a scant 0.1 inch thicker but practically an inch taller (5.4 inches versus the H4150's 4.5 inches) due to an integrated thumb keyboard that is spacious enough to make using it fairly comfortable. Neither unit has a visible wireless antenna; both have 64MB of RAM and 32MB of flash ROM. The H4350's lithium ion battery is larger and more powerful than its sibling's, but optional extended batteries are available for both.