It’s not just wives at home or relatives overseas that keep taxi drivers tied up on their cellular phones during work shifts. Many cabbies say that when they are chatting on duty, it’s often with their cab driver colleagues on group party lines. Taxi drivers say they use conference calls to discuss directions and find out about congested routes to avoid. They come to depend on one another as first responders, reacting faster even than police to calls from drivers in distress. Some drivers say they participate in group prayers on a party line.

“Sometimes one person recites, and a group will listen to him,” a Sikh cab driver from India, Satinder Singh, said. Mr. Singh, who lives in Queens and has been driving a taxi for five years, said that only in the past year or so, since he started using T-Mobile, has he participated in conference calls.

Aleksander Sverdlov, a Russian immigrant who has been driving a taxi for 15 years, said he has accumulated about 150 numbers in his cell phone, most of which belong to colleagues he conferences with on and off during his eight-hour shift. “I know everyone,” Mr. Sverdlov said over coffee and breakfast sandwiches in his cab at La Guardia Airport.

It is during this morning routine, waiting for the first shuttle flights to arrive from Washington and Boston, where many friendships between cabbies are forged and cell phone numbers are exchanged, Mr. Sverdlov said. Once drivers have each other’s numbers, they can use push-to-talk technology to call large groups all at once.

Mr. Sverdlov said he conferences with up to 10 cabbies at a time to discuss “traffic, what’s going on, this and that, and where do cops stay.” He estimated that every month, he logs about 20,000 talking minutes on his cell phone.

While civilian drivers are allowed to use hands-free devices to talk on cell phones while behind the wheel, the Taxi & Limousine Commission imposed a total cell phone ban for taxi drivers on duty in 1999. In 2006, the Taxi & Limousine Commission issued 1,049 summonses for phone use while on duty, up by almost 69% from the 621 summonses it issued the previous year. Drivers caught chatting while driving are fined $200 and receive two-point penalties on their licenses.

The Taxi & Limousine Commission is stepping up enforcement of the ban with undercover patrols and by tracking passenger complaints, according to a Taxi & Limousine Commission spokesman, Allan Fromberg. But many cabbies say they conference call anyway and hope they don’t get caught.

“It always stays within the circle of trust,” said a Bengali cab driver, Rahman Muhammad, who lives in Queens. “It’s a network system, unity by nationality.”

A Polish cabbie, Michael Kon, said he feels a sense of camaraderie with all cabbies. “We stick together as professionals,” Mr. Kon said. But when it comes to party lines, drivers like Mr. Kon are uninvited.

Drivers originally from countries like Israel, China, and America, who are few and far between, say they rarely chat on the phone with other cab drivers because of the language barrier. For many South Asians and Russian drivers, however, conference calls that are prohibited by the Taxi & Limousine Commission are mainstays of cabby life.

Faruq Ahmed, who is from Bangladesh, says he spends about four hours a day on a party line. “I put it on speaker, and under the clipboard, so they can’t see if I’m on the phone,” Mr. Ahmed said, explaining how he has managed to avoid receiving a summons from the Taxi & Limousine Commission. Cell phones, Mr. Ahmed said, are good for business, driver safety, and even benefit passengers because drivers learn from each other about what’s happening on the streets.

Mr. Ahmed also supplements his party line chats with conversation his CB radio. “Usually on the radio, it’s just one or two talking, and many many people listening in,” he said. Different languages are broadcast on different radio channels.

A transportation and taxi industry consultant, Bruce Schaller, said that the rate of recorded accidents involving taxis has steadily decreased following the cell phone ban, but he said the two are not necessarily correlated. “If talking on the cell phone increases job satisfaction, then drivers may stay in the business longer, and experienced drivers are better drivers,” Mr. Schaller said. “Even though passengers, including myself, find it annoying, there might be some benefits.”

As part of the Taxi & Limousine Commission’s new test fleet of technology-enhanced taxicabs, a new text-messaging feature allows the commission to alert cabbies of where and when they are needed. That could help cabbies collect more fares.

The technology has met opposition from cab drivers who say they do not want to pay up to $5,300 for the Global Position Systems they oppose. As for text-messaging capabilities, many cabbies said they did just fine getting the information they needed from each other in their native languages.