Meet the Ctronics Portable WiFi Doorbell: a handy tool that lets you see who is knocking on your door. It supports two way audio, motion detection, and iOS/Android devices. You can monitor your home, chat with visitors, and control your doorbell from anywhere. The device has a wide-angle lens camera. You will get notified on your phone when someone rings your bell. Sets you back under $150 at this time.
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