The cellular world is slowly being dragged, sometimes kicking-and-screaming, into the computing mainstream. Always-On applications are playing a big part.

I saw that at the small booth of Wherify. This company makes strap-on GPS devices. The sales material in their booth was filled with kids on skateboards whose mommies worry about them. But when I sat down to talk, CEO Tim Neher admitted that the message didn’t match the market.

The company has been deluged with requests from the families of Alzheimer’s patients, he said. In response the second version of the company’s product strips away the fashion statements.

It’s a tiny box, the size of the chewing gum samples you get from cheap houses at Halloween. He noted that one woman sewed a false pocket onto her father’s trousers, and talked movingly of a patient who was traced across the LA bus system from Hollywood to Santa Monica.

I suggested glueing a pin to the thing, and mentioned a company that has turned walkie-talkies into Star Trek-style communicators, worn on the front of the shirt. That sounded like a good idea to him.

More important, by thinking about old folks instead of kids, Wherify is moving from the world of safety and convenience to Medical Monitoring, a major Always-On application set.

Once you’ve moved into that mindset, you can think about monitoring other aspects of the patient’s health, maybe their heart rate, to check for signs of panic. Once you’re monitoring heart rate, the world of the hypertense (like me) starts to open up to you. Or consider the world of blood sugar, and here stands diabetes.

Currently the handheld devices in this market can’t communicate, and most tests require patient or a doctor’s intervention. Make it automatic, report automatically, alert when necessary. Use the cellular network to pass data, use the GPS to find the patient.

This is how Always-On applications evolve, when the light bulb goes off in some executive’s head and he is lured into a new direction. And it’s starting to happen.