Nest Hello review: Google's smart facial-recognition video doorbell

Google's new Nest Hello is a video doorbell that aims to be smarter than the rest with constant recording, face and object recognition. The Hello is a direct replacement for a wired doorbell, working with an existing chime and requiring constant power, making it one of the high-end options for smart doorbells. That need for power restricts where you can put it, unlike some more flexible options such as the battery-powered Ring Video Doorbell 2, but enables some much more powerful features. The Hello is a simple-looking modern doorbell featuring one large button with a glowing blue ring around it and a camera above it. It's about twice the size of a traditional doorbell and is screwed directly into the wall.