"The personal computer for the rest of the world isn't going to be the personal computer. It's going to be the cellphone," says John Sviokla, 47, the vice chairman of DiamondCluster International, a Chicago-based technology-consulting company. "Communication is more important than computation on the human hierarchy of need."

But before that can happen, the cellphone is going to have to change. Specifically, cellphone companies have to surrender their control over the phone's features and capabilities. If phones had standard ports -- such as USB connections -- innovators could develop their own applications without having to wait for the cellular provider to offer them.

"Think of what happened with personal computers when they opened up the architecture," Dr. Sviokla says. "Personal innovation flourished."

So what would he add if he could? He lists a scanner that would enable him to store business-card information in the phone, a global-positioning system, a radar detector, a flash-memory reader that would allow the phone to serve as a portable hard drive and a fingerprint reader "so I could lock my phone by touching it and unlock it by touching it," Dr. Sviokla says, noting that several vendors provide the technology, but it isn't available on any phones on the market.

"The phone companies cannot possibly market all the options that people might come up with," Mr. Sviokla says. "If they open the device, then the market of new adopters can discover the most popular combinations, and then the big guys can pick the popular things and merchandise them extensively."