The “Citizen” app, showing the type of crime reported, a map of its location, and the button to start live streaming the event if you’re nearby. (Citizen)

The woman called 911, frantic. Her baby was locked in the car. While emergency workers headed to the scene, a man nearby received an alert on his phone about the situation. He was an emergency worker too, with tools to unlock the car. The man went outside with his equipment and unlocked the car, to the mother’s great delight. She thanked him and drove off, before the emergency workers arrived, without even knowing why the man came to her rescue.

“This happened from an app,” said the app’s proud father and creator, entrepreneur Andrew Frame. The man had gotten his alert through the phone app “Citizen,” which monitors 911 police and fire calls in New York City and posts their locations as well as key details in real time, and also pushes alerts to those in the area. The relieved mother of the baby “had no idea,” Frame said. “She was the recipient of a ‘good samaritan.’ He didn’t even open the app.” Someone else told Frame the story of being in a Manhattan hotel and learning of a fire there before the hotel alerted the guests to it. “That’s using technology in a positive way,” Frame said.

Cautiously, Frame is moving Citizen forward. On Tuesday, he unveiled a beta version in San Francisco, the app’s second market. They have no plans to roll it out in other cities yet, or to promote it through mass marketing or other hype. “We’re still in the early stages of figuring it out,” Frame said in an interview. “We have to carefully assess how the app is being used, we have to make sure it’s not being hijacked in negative ways. We want to make sure it’s being used in a positive and productive way. To our delight, it is.”

Citizen had a rocky start when it began life last year as “Vigilante,” and seemed to encourage users to intervene with crimes in progress. Apple took it down from its app store after a day. The New York Police Department were openly unimpressed. “Crimes in progress should be handled by the NYPD and not a vigilante with a cell phone,” the department said last October.

But Frame retooled it as Citizen, which now makes it clear, both in on-screen warnings and its Terms of Service, that it “does not allow users to interfere with active crime scenes or disrupt law enforcement. Both are clearly forbidden in our Terms of Service, and we’ve been encouraged by the responsible engagement of our New York user base,” Frame’s company said in a release announcing the San Francisco roll-out.

The ability to know of, and avoid, an incident in progress may be Citizen’s best feature, though it’s one that will be hard to measure. But if I’m in New York’s Greenwich Village with my kids and I get an alert about an armed robbery at 6th Avenue and 8th Street, I’m going to detour away from there. That’s good information to have, and it’s free. There is also the potential for someone to try to intervene when getting such an alert, and possibly make matters worse. Frame knows this is coming, and said he’ll deal with it as needed.

The New York police press office, in an unsigned e-mail this week, recycled their previous comment that, “If an individual is the victim of a crime, would like to report a crime, or needs police assistance, the NYPD urges them to call 911 or speak to a police officer,” even though Citizen does not enable users to report a crime or call for assistance. It acts on already reported incidents broadcast by 911 dispatchers. The New York police email also added, “There are several sources of information regarding crime data available to the public. Please be referred to the links below.” though Citizen does not collect or distribute crime data. A follow-up email seeking clarification went unanswered.

“I think they’re studying and observing the impact,” Frame said of the NYPD, and he has had contact with police officials who don’t necessarily see it as a threat. “We don’t have a political viewpoint,” Frame said. “This is just about safety. Transparency and safety.”

Citizen San Francisco Launch Video from Citizen on Vimeo.

Citizen uses about 20 employees to monitor the unencrypted police and fire calls in New York’s five boroughs around the clock. When they hear something that could be a public safety issue, or just a curiosity for people nearby, they post it to the app and send out an alert to users nearby with an accompanying map of the area. Users can avoid the area, or approach and shoot video and livestream it on the app, which a surprising number of folks do. Frame said the app has about 120,000 users in New York, not counting outside observers like the True Crime blog in DC.

The posts are straightforward, careful not to sensationalize what little is known about an event as it is erupting. Here are the last five posts as I’m looking at the app right now:

“Possible Robbery; Prospect Ave. and Westchester Ave.; The suspect reportedly fled northbound on Prospect Avenue in a black Camry.”

“Teenager Possibly Stabbed; 269 Clarkson Avenue; Police at the scene have called for no further units to respond.”

“Theft; 5301 4th Avenue; Police have received a report of a theft of personal property.”

“Man Destroying Property; 92-49 215th Place; The man may be suffering from a mental illness.”

“Group Fight; Washington Ave & Park Pl.; The suspects are described only as a group of Black men and Hispanic men.”

[As I scroll down, there is another report of “Child Locked in Vehicle." What’s up with all the locked-in kids, New York?]

As events unfold, Citizen adds more detail about the emergency response and what is found. And sometimes it’s not an emergency, it’s just a big crowd or a blocked-off street, and Citizen can provide some answers as to what’s going on. As I look at the phone now, I see, “Electrical Union Protesters Gathering for Rally in Foley Square,” which apparently started out as “Incident Reported at Foley Square.” Additional officers were sent. Someone starting streaming video of it. And then someone at Citizen determined that it was a rally of electrical workers who “have been striking for workers’ rights and affordable health care for several months,” and posted that information too.

Frame said any fears of Citizen users jumping into the fray of a crime in progress haven’t been realized so far. “We haven’t seen that at all,” Frame said. “We’re watching very carefully.” The new promotional video for the San Francisco roll-out features a dramatization of users streaming video as they spot a car with a suspected child kidnapper, but not actually chasing the car, and which the police then use to find the kidnapper.

The app is about making more information available to more people. “The transparency movement is happening with or without us,” Frame said. “I think it’s here.”

And though Frame says, “We don’t have a revenue model yet,” he has lined up significant financial support from venture capital groups such as Kapor Capital, with backers such as former NAACP president Benjamin Jealous and entertainment mogul Russell Simmons, and more recently Sequoia Capital, which was an early investor in nascent outfits such as Apple, Google and YouTube, and has committed $12 million in Series A funding. “If you can build value that’s unique and grow it,” Frame said, “business and revenue opportunities start to emerge.”

It will be interesting to see if a West Coast city takes to Citizen as New York City apparently has. I’m not sure why it wouldn’t.