A New Jersey man foiled a robbery at his home thanks to surveillance cameras and free app on his smartphone that alerted him to the break-in and allowed him to yell at the startled burglar through the cameras' speakers.

Nisarg Swaminarayan, 29, was eating dinner near his Parlin, N.J., home with relatives this weekend when he says his Dropcam security system sent an alert to his smartphone, telling him the sliding door of his home had been opened.

"It's pitch dark, but these cameras have a night vision," Swaminarayan told ABC News' affiliate WABC-TV.

Surveillance video shows the alleged burglar opening the unlocked sliding glass door and entering the home. While he appears to try to outsmart the homeowner by turning around a surveillance camera, he doesn't know two other cameras are rolling and Swaminarayan is watching remotely.

Swaminarayan said he watched as the invader grabbed his electronic equipment, so he tapped into one of the camera's loudspeakers and screamed. "I simply told him, 'I can see you, please, leave my home,'" he recalled.

It did the trick, scaring away the intruder.

Security expert Chris McGoey said technology like the kind Swaminarayan used is becoming more common.

"It's being embraced more and more by the mainstream as situations like this happen and we see proof of their effectiveness," McGoey told ABC News.

Thanks to the surveillance footage, police quickly tracked down the suspect, identified by police as Oliver Alavez-Luengas, 22, who is being held in a New Jersey jail on $25,000 bail.

For Swaminarayan, he has a free app, his phone, and a few mounted cameras to thank for stopping the alleged robbery. Total cost: $150.

"It was a real thing and it happened to me," he said.