Ever wish you could find directions to the nearest bookstore or coffee shop without asking a stranger? Maybe you're having trouble keeping tabs on your adventurous children?

Your cell phone could be the answer to such problems, as wireless companies have started to make commercial use of technologies originally developed to help emergency workers find callers in danger.

While relatively new, these mobile services have begun to build a following by making it easier for people to find their way around a strange city, meet up with friends, or get directions to a new restaurant or shop.

One new user, Milton Williams, who installs and maintains air conditioning units for Athens, Georgia-based D&B Heating and Air, recently threw out his old paper maps. He now uses a cell phone navigation system that verbally directs him to out-of-the-way customers once he's punched in their address.

"Everything is time here, going from one job to the other. It helps me tremendously," said Williams, who about a month ago signed up for a navigation service from Verizon Wireless, a venture of Verizon Communications Inc. and Vodafone Group Plc.

Roger Drissel, another worker who spends a lot of time on the road, uses Verizon's service for driving directions two to three times a day when he's on out-of-town jobs. He also uses it to find somewhere to eat by searching the phone for a restaurant type and following turn-by-turn directions.

"I don't have to worry about where I'm going, about where things are. All I need is the address on the phone and it tells me how to get there verbally," Drissel said. Drissel, who manages information systems for Saber Corp., even stopped using a dedicated car-dashboard navigation system when he started using the Verizon cell phone service.

"That's another little box in my life. I don't even notice this is in my phone." he said. But while he finds the wireless service easy, Drissel said it has not always helped him save time. He said, "It didn't always know that there may have been shorter routes than the one it gave me, but the route that it gave me has always been right."

Nevertheless, judging from the growing number of customers, users appear willing to look past some of the shortcomings of cell phone navigation.

Networks In Motion, a privately held mobile navigation developer, says it has had a million customers, including one-time users who paid $3 a day and those who pay about $10 a month. Most of these customers come from Verizon Wireless.

Other providers include Sprint Nextel Corp, whose service includes local search functions from Ask.com and InfoSpace Inc that help phone users find shops or services based on where they are.

Helio, a venture of SK Telecom and EarthLink Inc., is among the companies that have taken the technology even further by letting groups of friends broadcast their location to each other to arrange spontaneous meetings.

Sprint, Verizon and Walt Disney Co. also offer services that let parents monitor the location of their kids, so long as they are equipped with cell phones. If a child wanders too far, an alert may be sent to the adult's phone.

Carroll Hannon, an Indianapolis-based mother of five, said she hopes to subscribe to the Disney service to help her look after her daughters, aged 11, 13 and 15. "We liked having it, especially when we were on vacation," said Hannon, who recently tested phones from the three providers for a Money Magazine story.

"The children might be taking a walk on the beach and all I had to do was have them take their cell phone," she added. "It was just peace of mind." But the friend and child locater services may not be for everybody, said IAG Research communications research vice president Roger Entner.

"It depends if you're the 'Every Breath You Take' or the 'If You Love Someone, Set Them Free' type person," said Entner, referring to two popular, Sting-penned rock songs to exemplify hands-on and hands-off personalities.

The customers interviewed for this story said they were not given incentives by the provider to talk about the services.