"The cameras offer a wide view from wherever they are positioned. Homeowners get phone alerts with streaming video if the doorbell rings or the device's heat sensors detect a person or a passing car. Ring's basic doorbell sells for $99, with recurring charges starting at $3 a month for users who want footage stored. Ring says it stores the recordings for two months. Many law enforcement agencies nationwide said the idea to partner with Ring came after the company promoted its product at law enforcement conferences. Some departments have chosen to simply use Ring's Neighbors app, which encourages residents to share videos of suspicious activity. Other agencies agreed to provide subsidies, matched by Ring, to offer hundreds of discounted cameras in hopes of tapping into footage of residential streets, yards and sidewalks. And some police chiefs raffle off the devices. Ring would not disclose the number of communities with such partnerships. Sharing video is always voluntary and privacy is protected, according to the company and police. "There is nothing required of homeowners who participate in the subsidies, and their identity and data remain private," spokeswoman Brigid Gorham said.