PDA Could Follow Path of PC

A DECADE ago, corporate managers took to the personal computer like kids to candy, igniting a technology revolution. Today, several companies hope they will do the same with an emerging portable electronic device called a PDA.

What does a Personal Digital Assistant do? And do you need one?

A PDA is not a stripped-down personal computer. It's a hand-held device that can keep a calendar, receive electronic mail, or send a fax -- plus other tasks.

''A big part of our business will be in the corporate [world],'' says Randy Smith, senior marketing manager with Motorola Inc.'s wireless data group here in Schaumburg, Ill. Businesspeople will have to decide that a PDA with the ability to communicate electronically is worthwhile before a general consumer market develops, he predicts.

In the past four months, Motorola has begun selling two hand-held devices that employ the two leading PDA systems that have emerged so far. The Envoy uses General Magic's Magic Cap; the Marco is based on Apple's Newton. Both devices are less than half the size of a notebook computer and use a pen-pointer instead of a keyboard. Their key selling point is wireless communications, allowing users to send and receive electronic mail without plugging into a telephone.

Several PDAs already have fallen by the wayside. But despite a tiny market, developers are writing new and intriguing software.

Some trends are becoming clearer, industry observers suggest. It doesn't matter if a PDA can understand handwriting. What does matter is whether it can send and receive data -- especially without relying on telephone lines.

''People aren't into buying gadgets anymore,'' Mr. Smith says. ''The two-way wireless seems to be one of the big differentiations'' among PDAs.

''Everyone wants the wireless,'' confirms Richard Frazita, research analyst at Link Resources Corporation, based in New York.

At the moment, the market for PDAs doesn't reflect this -- partly because wireless communication is expensive, Mr. Frazita says, and because the PDA market is so ill-defined that it lumps together different kinds of devices.

Link Resources breaks the market down into six categories: organizers, personal agents, personal communicators, electronic books, electronic notepads, and entertainment agents.

Last year, United States consumers bought 815,000 such devices, Link estimates. Nearly 80 percent of them were electronic organizers, such as the Sharp Wizard, which includes a calendar and simple computer programs.

All six categories will grow, the firm predicts, but the biggest growth will be in personal communicators, which includes BellSouth's Simon -- a cellular phone that can also display electronic mail. By 1998, Americans will snap up 1.8 million personal communicators, nearly half the expected PDA market, Link estimates.

Such sales will still be relatively small compared with the market for portable computers, which already this year will top 9 million units worldwide, according to International Data Corporation, a Framingham, Mass., research firm.

Some observers figure PDAs will face stiff competition from portable computers. ''The laptops will be dominant the next five years,'' says Carl Perkins, president of New Media Corporation, an Irvine, Calif., manufacturer of credit-card-sized peripherals, called PC Cards, which are used in both laptops and PDAs.

Although Link is more hopeful for personal communicators than personal agents, which fall somewhere between a communicator and an organizer, Motorola and Apple Computer Inc. disagree. Their PDAs are classified as personal agents.

Apple, which pioneered the market with its ground-breaking Newton, has endowed the latest version with a PC Card paging device that receives wireless electronic mail. The system, from Paging Networks Inc., is expected to be able to handle two-way wireless communications nationwide next year. Sony Electronics' PDA -- the Magic Link PIC-1000 -- has an add-on PC Card pager from SkyTel Corporation.