TrapCall, which was launched Tuesday, was designed to unblock and reveal callers' identities and numbers even after individuals have tried to block the information.
Telephone users have been able to block personal information from showing up since the early 1990s, when Caller ID was introduced. In the past, people could rely on dialing either *-6-7 before placing a call or asking their phone company to always hide their number when they make outgoing calls to shield their identity.
It is TrapCall's promise to allow people to always see the phone number and even the home address of the person calling them, even if that person has blocked Caller ID, that has domestic abuse organizations upset. Abuse victims advocates argue that victims who routinely rely on blocking Caller ID when communiciating with abusers could be put in harm's way by TrapCall.
"I'm quite concerned about TrapCall," Cindy Southworth, the director of the Safety Net Project at the National Network to End Domestic Violence in Washington, D.C., told ABCNews.com.
"When Caller ID first came out, phone companies worked very closely with domestic violence advocates to make sure victims could make anonymous calls and this strips away that anonymity," said Southworth.
But the president of the company that makes TrapCall said the technology was developed with domestic abuse victims in mind, to let them always see who is calling them. And if they are concerned about preserving their anonymity when they make calls, he said, the company has another product that can trick Caller ID.
According to Southworth, anonymity is often very important to domestic abuse victims who, even though they have left their abusive partners, are still required by law to remain in contact with them in situations where child custody issues exist.
"Anonymity matters in many cases," Southworth said. "Sometimes, women are mandated by a judge to discuss where they're going to drop off the children for visitation and they have to make that call."
"Now I'm advising victims to use a third party -- a mother, a sister or a friend -- to make the call and not to trust that their number really is blocked," Southworth said.
TrapCall Unblocks, Identifies Mystery Callers
According to Meir Cohen, president of TelTech, the New Jersey-based company that manufactures TrapCall, the product works by sending a blocked number through a software system that then identifies the number. That number is then sent to the person receiving the call, who can then decide whether to answer.
"If you get a call on your phone and the number is blocked, you hit 'decline' and while the caller hears ringing in the background and doesn't know anything has happened, a few seconds later your phone will start ringing again and this time it will show the phone number," Cohen said, explaining what happens when an incoming call is caught in TrapCall.
The free version of TrapCall reveals the name and number of the caller, while two other more expensive packages, priced at $9.95 and $24.95, offer more advanced features, such as voicemail transcription sent to your e-mail and the ability to record all your incoming calls at the touch of a button.
"You can decide you want to record a conversation and then retrieve it online and download it and do whatever you want with it," Cohen said. "That's a huge feature."
So far, the service, which can be downloaded on the company's Web site, is only available to AT&T and T-Mobile customers, but Cohen said other carriers will be added soon.
Cohen said another feature he anticipates will become popular is blacklisting, by which phone numbers a user does not want to receive calls from are blocked. Instead of reaching the person they are calling, the caller hears a recording stating that the number has been disconnected.
Blocking Caller ID: A Safety Tool?
But people like Southworth say that the more features this product offers, the worse, arguing that it could result in more cases like the 1995 murder of 21-year-old Kerisha Harps, who was killed by her ex-boyfriend when he saw the number where she was calling from on a Caller ID display.
According to Associated Press reports during the investigation, Kevin Roberson was looking for Harps in a friend's apartment when the phone rang; Harps was calling, thinking she would reach her friend and not her ex-boyfriend.
Roberson read the Caller ID display while he was in the apartment looking for Harps and recognized the telephone number, which later led him to locate Harps.
Roberson was later convicted of the shooting death of Harps and sentenced to life in a Texas prison.
When asked about the critics of his company's product, Cohen said he just "doesn't understand them."
"We made this product with [domestic abuse victims] in mind," Cohen said. "They've been complaining that they have stalkers and are getting harassed, so we made a product to unblock Caller ID [so they know who is calling them].
"We made a product so they can record their conversations and go to authorities," he said. "They're just getting worked up."
But when those victims have to make outgoing calls to their abusers, said Southworth, which they often do to arrange child care, is when Cohen's product becomes most dangerous.
"Domestic violence and stalking is all about power and control," she said. "The offender wants to reach the victim in any way to contact her and intimidate her and instill fear, and if you have to negotiate a drop off of a child, this product becomes dangerous to victims in hiding."
Cohen said a solution to this problem is another TelTech product known as the SpoofCard Caller ID, which allows users to make their phone number show up as someone else's when it appears on Caller ID.
"If someone who is worried about being found has to call out, they can always use our SpoofCard," Cohen said. "They can put their office number in the program and that's what will show up on the Caller ID of the person they're calling."
Marc Rotenberg, executive director of the Electronic Privacy Information Center (EPIC), said the primary drawbacks of products like TrapCall is that they do not distinguish between situations where it makes logical sense to provide anonymity and those that do not.
"The problem with these devices is that they basically make no distinction between people who might have a good reason for anonymity," he said. "The whole thing seems like covert surveillance.
"The default clearly has to be that people retain their anonymity, unless they have chosen to give their identity," Rotenberg added. "This is a deceptive way to obtain someone's identity."