For a peek at the future of wireless applications, take a look at the technology behind the familiar brown United Parcel Service Inc. delivery trucks. The $37 billion-a-year package-delivery company is building one of the largest Wi-Fi networks in the world, which, when finished next year, will constitute 15,000 wireless-access points at 1,700 warehouse facilities around the globe.

Package loaders working in some UPS facilities wear Bluetooth-enabled "rings" on their hands that scan delivery information from package labels as they load and unload trucks. Scanned information is transmitted to wireless terminals strapped to their belts. Those terminals are armed with 802.11 wireless connections, which send information to a server. From there, package information is transmitted to UPS's wireline network and back-end systems. UPS has deployed the technology in about 500 facilities throughout the United States and Europe.

"Whenever we see business value in wireless technology, we'll strongly consider its adoption," says John Killeen, director of global network systems for UPS. That kind of connectivity is required because UPS, on an average day, delivers about 14 million packages, and its Web site gets 9 million tracking requests. "Customers know the location of their package within seconds of its location being updated," Killeen says.

Wireless applications help UPS customers locate their packages, John Killeen, director of global network systems for UPS says.

Welcome to the future of wireless applications. Software vendors are just beginning to dream of the kinds of applications they might develop to leverage the capabilities of third- and fourth-generation wireless-network technology. Carriers such as Cingular, Nextel, SprintPCS, and Verizon are rolling out 3G technology that has data speeds of 300 to 500 Kbps and up, and the first 4G wireless networks that promise bandwidths of 1 Gbps are on the horizon.

Wireless communications at such speeds will change forever the way data is accessed through applications that can be run virtually anywhere. "People are talking about extending existing desktop applications, all of their business applications, and the desktop-computing experience to the mobile worker. Everything from databases to content, whatever they happen to need, will be available to them," says Andy Fuertes, senior analyst with IT-research firm Visant Strategies.

Other technologies, such as WiMax, could one day blanket metropolitan areas with high-speed wireless access, providing more ubiquitous connections than Wi-Fi hotspots in coffee shops and other locations today.

Forward-looking companies already are reaping the benefits of wireless applications. Pitney Bowes Inc. estimates that a system connecting 2,000 field-service representatives using notebook PCs and handhelds to a real-time scheduling, maintenance, and parts-information application has boosted productivity by 8% and reduced last-minute orders for emergency parts by 20% to 25%. Pitney Bowes invested about $20 million to build the system, which incorporates Siebel Systems Inc. field-service applications and Antenna Software Inc.'s Antenna A3 for Siebel wireless technology, and the company estimates it can cut $100 million in costs over the next decade through more efficient management of service calls and spare parts.

UPS is rolling out the fourth generation of its electronic clipboard equipped with Bluetooth and 802.11 Wi-Fi connectivity. The latter will enable last-minute delivery changes to be sent directly to a driver's clipboard, Killeen says. New global positioning system capabilities built into the device will help dispatchers know the exact location of any truck and warn a driver about to deliver a package to the wrong location.

Most major software vendors already offer some level of wireless access to their applications. Siebel debuted its first wireless app in 2000, providing connectivity to customer data, such as sales and service histories, in the company's customer-relationship-management system. Siebel has since built wireless applications for vertical industries such as pharmaceuticals, health care, and consumer packaged goods. Current releases of Siebel's products let users work offline with mobile devices and then sync up with the main Siebel system using store-and-forward technology.

The next step for Siebel is to add data-analysis capabilities to its wireless sales and service applications, says Bill Hou, Siebel's general manager for service- and call-center products. But that will require wireless networks with more bandwidth and mobile devices with more computing power than generally are available today, Hou says. Higher-bandwidth wireless networks also will make it possible for mobile workers to receive documents automatically as they complete transactions on the spot.