Window & door open and close A sensor for your house. IoT devices offer a number of new opportunities for healthcare professionals to monitor patients, as well as for patients to monitor themselves. Door and window sensors let you know when people are entering and leaving your house and can even turn lights on and off as doors are opened and closed. Video doorbell It's a video doorbell! The ring is one of the original video doorbells on the market, but there are several good options now. These cool devices allow you to see who is at your door from your smartphone. Whether you are inside alone and want to screen who is at the door, or if you are at work and someone is at your house. You will know.