Just how big can mobile E-mail get? The BlackBerry may seem ubiquitous in some circles, but fewer than 7 million businesspeople worldwide use mobile E-mail. Imagine 20 times that number--and having to manage 20 times that many PDA users. That's the future many companies face.

The price of getting hooked up is dropping, and startups are touting products that let businesses use mobile E-mail for more than just messaging. BlackBerrys and similar devices aren't just for busy professionals anymore; service technicians and other workers are increasingly using them to update work tickets and respond to incoming assignments. Research In Motion Ltd. has begun targeting these "corridor warriors" with a BlackBerry model that works on wireless LANs instead of cellular networks.

Nokia's Dave Grannan, general manager of mobile E-mail, made the bold prediction at last week's Interop trade show that 100 million business users of mobile E-mail was "very achievable" in the next four years. Lower-cost devices will help drive the trend, he says. Nokia plans next year to make mobile E-mail a standard application on its business-class cell phones, some of which will come equipped with QWERTY keyboards. Nokia isn't talking price, but more E-mail-capable phones are expected to sell for less than $200.

Even a more-conservative projection shows an adoption curve with a sharp incline. The Radicati Group, which earlier this year forecast 39 million mobile E-mail users worldwide by 2008, just upped that forecast to 123 million by 2009, based on updated information from device vendors, network-service providers, and global companies. Growth is being driven by salespeople, insurance brokers, and others who want E-mail on the road without having to drag along a laptop and find a Wi-Fi hot-spot. "It's not just for executives anymore," says CEO Sara Radicati.

Disruptions Ahead?
With exploding demand for mobile E-mail comes IT stress, everything from mild upgrade discomfort to considerable investment risk. Research In Motion, the market leader with 3.7 million mobile E-mail users, is fighting a court injunction that could prevent it from selling and supporting its BlackBerrys in the United States, following a patent lawsuit filed by NTP Inc. RIM and NTP are waiting to hear whether a U.S. District Court will issue an injunction. NTP wants a big payday: It successfully contested in federal court last month a $450 million settlement between the two companies, a deal NTP claims was never completed. RIM's fate also hinges on the U.S. Patent Office, which has issued a preliminary rejection of some of NTP's patent claims after review but hasn't finalized that decision.

Dr. Sameer Bade, assistant VP of clinical informatics at MedStar Health, is concerned. More than 400 of MedStar's executives and managers use BlackBerrys for E-mail and calendaring at hospitals and health-care clinics around Washington, D.C., and Bade predicts 30% annual growth as other types of employees request their own devices. RIM has assured MedStar and other customers that it was preparing software workarounds to maintain its messaging service in the United States should NTP prevail, but the plan was too short on details for Bade's satisfaction.

After a new spate of legal wrangling between vendors last week, IT managers considering PDAs for E-mail might want to have a chat with corporate counsel first. Visto Inc., a mobile E-mail software company, filed a federal lawsuit claiming Microsoft's Windows Mobile 5.0 violates its patent covering how mobile devices retrieve E-mail from behind company firewalls. Microsoft declined to discuss the suit until it could review it but said it "stands behind its products and respects the intellectual-property rights of others."

Earlier in the week, Visto licensed NTP's wireless E-mail technology, and NTP took an equity stake in the company. Nokia and mobile software and services vendor Good Technology Inc. also have licensed NTP patents, apparently reinforcing NTP's claim against RIM. Dave Werezak, VP of RIM's enterprise business unit, declined to discuss the case or rumors of an impending settlement. "There's no advantage for anyone to turn the service off," Werezak says.

Management Issues
Data security is another factor. The rapid growth of mobile E-mail is creating a greater need for encryption between mobile devices and corporate servers, a higher level of security than is common in the world of cellular networks and phones. Security concerns surround other types of wireless networks, too. Remember the "Evil Twin" attacks of about a year ago, when hackers at Wi-Fi hot-spots replicated the identity of valid access points?

IT managers must also ensure that they can wirelessly wipe out the information on a device should it get lost or stolen. And they must acknowledge that mobile devices create yet another repository for spam, worms, excessive E-mail strings, and all the other evils that come along with E-mail's good.