Bangalore: Dede Haskins's cellphone has been her constant companion for more than a decade and she always considered herself a careful driver - even using a hands-free set. But after missing too many exits she signed up for ZoomSafer, a free service that uses her phone's GPS sensors to determine whether she's at driving speeds, and then disable her cellphone until she stops the car.

"I really love my cellphone. But I know I'm not driving safely if I'm using it while behind the wheel," said Haskins, CEO of a software company in Washington. Of course, there is a simpler, no-cost solution to limiting phone use while driving: the off button. But going cold turkey is hard for many Americans who have become addicted to their gadgets. So technology companies are trying to solve a problem caused by technology with more technology.

But the solutions reflect markedly different answers to a simple question: How much can drivers be trusted? One group of companies assume that some people know they can't help themselves, and therefore want a service to automatically disable their cellphone when it is in a moving car.

But other companies say that the habit can be made safer with hands-free technology. Ford and Microsoft, for example, are selling systems that rely on voice commands to dial phones. Hands-free devices are far more popular. But it is cellphone-muzzling technology that has caught the eye of large auto insurers. That's because some studies show that talking on phones while driving is dangerous, even if the driver is using a headset and has both hands on the wheel. One insurer has even said it will offer discounts to customers who use a call-blocking service.

A number of fledgling companies like ZoomSafer, Aegis Mobility and obdEdge employ systems place restrictions on phones based on the phone's GPS signal, data from the car itself or from nearby cellphone towers. Any incoming calls are then routed to voice mail or a message explaining that the phone's owner is driving. Exceptions can be made for certain numbers.

Passengers in cars can override such systems, but in many cases doing so automatically sends an e-mail message to the account administrator, alerting them that the cellphone is in use.

Employers that want to make sure that their drivers abide by bans on cellphone use are obvious potential customers. Community Coffee, a Baton Rouge, coffee roaster and distributor, has had such a ban on its 400 trucks for three years, which the company says has helped in reducing accident rate by 30 percent.

It started testing a call-blocking system from obdEdge, called Cellcontrol in August. ObdEdge charges companies $85, plus about $5 monthly, for each vehicle equipped with Cellcontrol.

"We realized that we had to go beyond education and policy," said Jamey LeBlanc, Risk Manager for Community Coffee. In effect, addiction to gadgets is creating a new gadget industry.

"If we could control ourselves, we wouldn't need any of this technology. We know that it is a bad habit, but we crave being connected. Other companies insist the habit is not so bad and can be mitigated by employing voice recognition and speech-to-text technologies in cars," said Donald Powers, Managing Partner at obdEdge.

Such systems are typically developed and promoted by some of the biggest names in electronics and automobiles, as well as well-financed trade groups like the Consumer Electronics Association and Cellular Telephone Industries Association (CTIA), the wireless-industry group.

In 2008, 918,000 hands-free systems were installed in cars, according to the Consumer Electronics Association. By the end of 2009, the industry group estimates that figure will climb to 1.6 million systems. In many cases, hands-free kits are packaged with other options that together cost around $1,000. "We are trying to take what people are doing and make it safer," said Doug VanDagens, Director of Ford's Sync Project. But not everyone agrees that this technology is the safest option.