For 40-year-old Mao Ya, the facial recognition camera that allows access to her apartment house is simply a useful convenience.
"If I am carrying shopping bags in both hands, I just have to look ahead and the door swings open," she said. "And my 5-year-old daughter can just look up at the camera and get in. It's good for kids because they often lose their keys."
But for the police, the cameras that replaced the residents' old entry cards serve quite a different purpose.
Now they can see who's coming and going, and by combining artificial intelligence with a huge national bank of photos, the system in this pilot project should enable police to identify what one police report, shared with The Washington Post, called the "bad guys" who once might have slipped by.
Facial recognition is the new hot tech topic in China. Banks, airports, hotels and even public toilets are all trying to verify people's identities by analyzing their faces. But the police and security state have been the most enthusiastic about embracing this new technology.