The iPAQ h4150 chalks up a score as the thinnest and lightest Pocket PC on the market to include integrated Wi-Fi (802.11b) and Bluetooth connectivity, while the iPAQ h4350 model is HP's first - and the world's second - Pocket PC to feature an integrated thumbboard. For increased usability, the keyboard also features a backlight.Sharing almost identical specifications, the two handhelds are powered by Intel PXA255 XScale processors running at 400 MHz, and offer 32 MB of Flash ROM combined with 64 MB of RAM, of which 56 MB is available to users.