When Sean Cohen isn't answering phones at work, he's buying them from customers.
Cohen purchases used 15 to 20 cellphones and tablets every day, generally for pennies on the dollar, unless they're almost new.
But what some sellers may not know is that their device can be used as a home surveillance camera.
Jeff Zisner of AEGIS Security and Investigations says old cellphones and tablets with cameras can be re-used as security cameras for free.
"You set the camera up using Wi-Fi so you don't need to have a cellphone activated on an account, you don't need a monthly fee," he said.
All you need is to download an app. During a demonstration, we chose the Alfred app for Android - it's free.
Zisner set up a tablet in the NBC4 I-Team office and a phone in areas around the newsroom.
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"The app will alert you that there is motion that's in your house that's not authorized," he said.
You can monitor it live on your cellphone from work or elsewhere.
One of the benefits about using your old phone is that it doesn't just give you video, it gives you audio, so as you see a burglar in your house you can tell them to get out.
"And then the next call you make is to law enforcement so they can respond," Zisner said.
If police arrive too late, you still have a recording of exactly who burglarized your home and peace of mind - all for free.
You can turn your phone into a mobile home security camera with the following apps:
- Pocket Spy Cam
- Motion Detector