By Bobeth Yates

MIAMI (CBSMiami) – An app that claims to alert you in seconds when a crime is in progress nearby is making its debut in South Florida. However, the app is causing some controversy in other cities that have it.

Have you heard gunshots or a helicopter hovering around, wanting to know in real-time what’s happening? Well, there’s an app for that.

READ MORE: 'I Am A Conqueror': UFC Fighter, Miami Native Jorge Masvidal's Rise To Success, Sights On UFC Gold

“My phone went off with a Citizen notification saying that there was an active shooter event going on,” said a user of the nationwide app called “Citizen.”

Citizen provides real-time alerts of police activity. Anything from fires to shooting. It even allows people to upload a video of the scene.

“People want to be aware. People love situational awareness. They like to know what’s going on around them,” said Prince Mapp with Citizen.

Mapp said they have more than 7 million users who get information that they normally have as it happens.

“What we do is send 911 alerts straight to your smartphone so you can understand why there’s a police car in your area or why there’s a helicopter hovering above your house,” he said.

READ MORE: No Appointment Needed Now At Most Broward Drive-Thru Vaccine Sites

Mapp adds the app has even helped to solve crimes and locate missing people and pets.

Citizen officials said they recently launched in Miami and now have more than 33,000 local users. And come next week, they are adding surrounding cities.

“We decided we have to expand Miami, so we went to the greater Dade County, Miami Gardens, Kendall,” Mapp said.

But because the app provides constant information similar to a police scanner, some accused of increasing people’s anxiety.  And others say it’s a form of big brother who is always watching.

Still, some users are celebrating the service.

“I’m a driver for rideshare. Since I’m sitting often, it helps out when I’m going to different neighborhoods. I could’ve been trapped in my safety, could’ve been in danger,” another Citizen user said.

MORE NEWS: 2 People, Dog Shot By Man Who Got Into Gun Battle With Officers In Hialeah Gardens

The Dade County expansion includes 17 additional cities, and officials say the service is also available in Spanish.