Some new 'smart' cell phones need remedial help.(Up front: news trends advice)(Buyers Guide)

Combine a wireless phone with a personal digital assistant, or PDA, and yon get a device that promises to do it all: keep your personal information in one place while functioning as a "smart" phone for calls, text messages, an appointment calendar, address book, e-mail, and Web surfing Some pop in an MP3 music player or digital camera.

But even the best of the seven smart phones we tested weren't at the genius level. A few came close to flunking, None are less expensive than maintaining separate cell phones and PDAs.

Overall, the many functions these phones can handle are their strength and their undoing. The handiest phones make it easiest to use the PDA; the worst are phones with a PDA tacked on.

Our lineup included three phones using the Palm operating system, two using Microsoft software, and two using Symbian. The phones cost from $300 to a staggering $800.

How easy to use? For entering appointments and addresses, Palm units were best. They use the Palm Graffiti handwriting system or, in the case of the PalmOne Treo, a small keyboard. The other models provide only the standard telephone keypad, which is inadequate for entering data,

How convenient? The Samsung phones, which resemble conventional folding phones, and the oversized Kyocera were best here. Worst was the Siemens. Its phone number keys flank the display screen, an awkward design. All phones except the Samsung i500 have external-memory-card capability for, say, transferring photos.

The best connections? We like the top-rated, tri-mode Samsung and Kyocera models. They stand a better chance of making a connection because they can connect digitally in two frequency bands and in analog mode.