(MONEY Magazine) – Cell phones? Nope. DVD players? Not a chance. The iMac? Maybe. But you have to look far and wide to find a gadget that has won as many hearts as Palms have in the past few years. Devotees of these affordable hand-held computers have established countless online groups to talk about their Palms. And roughly 80,000 fans write software for Palms--a startling number that's even more notable when you consider that most give their software away for free.

In case you haven't noticed, personal digital assistants (PDAs) in general--and Palms in particular--have become a certifiable phenomenon. Zealots aside, even ordinary users love their Palms. And why not? Yes, these PDAs keep track of appointments and store addresses and phone numbers. But Palms can also spare you embarrassment by reminding you to send flowers on your anniversary. They can entertain you with a game of Tetris. They can break the ice: Pull out a Palm at a party, and you're bound to strike up a conversation. Meet someone you like, and you can beam a virtual business card across the table. When you get home, you can download everything into your computer.

Palms are, dare we say, cool. It's no wonder, then, that in just four years Palm has sold 7 million PDAs, a growth rate that rivals the boom years of the Walkman and compact disk players. By 2004, Palm buyers are expected to number 17 million, according to market analyst International Data Corp.

Of course, Palms aren't the only organizers out there, but the very word Palm has become shorthand for PDA. Palm devices have a 70% market share. The next hottest competitor, the Handspring Visor, runs on the Palm operating system (OS), as will the new PDA due this fall from electronics behemoth Sony. (For more on the four most important PDA makers, see the table on page 94.)

The key to the Palm OS dominance is simple. Most people, according to Forrester Research, use a PDA as a calendar, address book and to-do list. From the time Palm brought its first PDA (then called a Pilot) to market in 1996, the company bet that consumers wanted a device that did a few things well, was easy to master (Graffiti handwriting software took care of that) and could be connected with a PC or Mac. When Microsoft countered with Windows CE, a miniature version of its Windows operating system, later that year, it failed to catch on. Consumers didn't want Excel spreadsheets and Word documents crammed into slow computers.

Microsoft is still gunning for PDA buyers, as are other big consumer-electronics firms. To that end, last April, Microsoft launched Pocket PC, a streamlined version of Windows CE.

But if you think this heightened competition makes picking a PDA more confusing, forget it. Most buyers should stick with the Palm platform, which means a Palm, Handspring or the upcoming Sony. PDAs running on Pocket PC, such as the $499 Compaq iPAQ and the $499 to $599 Hewlett-Packard Jornada, do offer multimedia capabilities such as color screens for displaying digital photos and built-in MP3 players--but how many people really want them? Not only are Palm devices easier to use and cheaper--anywhere from $149 to $449--but there's also more software available. (See the box at left for our favorites.)

Your next quandary may be whether you want to use your PDA for wireless Web access. Forget that too. Despite what providers, including Palm, will have you believe, PDA wireless modems are prohibitively slow. Plus, you're unlikely to get a signal outside of urban areas. With monthly service costing as much as $60, going wireless with a Palm VII can be pricier than using a Web-enabled cell phone. Plus, cellular networks are more widespread. "Wireless for handhelds has a big chance of not materializing," says Dataquest hand-held analyst Mike McGuire. Determined to get wireless Web access on a Palm? The OmniSky modem (see page 93) is the best way to do so.

With these guidelines in mind, here are your best Palm OS choices:

--The basic user. If all you want is a calendar, address book and to-do list, your choices come down to the Handspring Visor ($179, including cradle) and the new Palm (about $150), which the company is releasing in August to compete with the Visor. This new Palm, while an okay choice for entry-level users, feels a bit flimsy compared with the Visor, which has another advantage Palm can't match: flexibility, in case you outgrow your calendar. Thanks to the Springboard, an expansion slot in the back of the unit, you can upgrade any Visor by inserting a module. Handspring is selling Visors only at www.handspring.com and through a few retailers, including CompUSA and Staples. So you'll have to pay list for the PDAs and most peripherals.

--The serious user. If you think you'll add more software--and want to invest in a PDA that won't be obsolete in a year--buy one with 8MB of memory vs. the basic Visor's 2MB. In this category, the $399 Palm Vx is the way to go. Not only is its sleek, anodized aluminum casing a crowd-pleaser, but it's the lightest, thinnest, smallest and sturdiest device out there. Unlike most PDAs, it has a long-lasting lithium-ion battery that recharges in the cradle. The Palm Vx is so popular that not even online retailers are discounting it. One site, www.buy.com, offers free shipping--the best savings we could find.

To spend less for 8MB of memory, go for the $249 Handspring Visor Deluxe, which comes in orange, green, blue, graphite and ice. Plus, its USB port makes for a faster sync than the Palm's serial port offers. But the Visor is clunkier and bigger than the ultra-stylish Palm Vx--reason enough for many devotees to pay more.