Downloadable and cloud-based software for operating home security systems and smart doorbell systems; downloadable software enabling users to acquire, store, and communicate health data to another user via networked devices; Computer software for capture and processing of machine-readable codes; Computer hardware and software for controlling networked devices; devices for controlling home security, video cameras, optical cameras, code readers, temperature scanners, and electronic sensors; computer hardware and software for processing, reproducing, synchronizing, recording, reading, translating, organizing, downloading, uploading, transmitting, streaming, receiving, playing and viewing images, audio, video and data files; wireless communication devices and software for voice, data, or image transmission; electronic voice and data transmitters and receivers; electric doorbells, motion sensors, sensors, detectors, and speakers, video recording devices, video receiving devices, cameras, night vision cameras, infrared cameras; personal security alarm system and camera mounts and stands all connected to a wireless network; computer software for use in sharing and transmission of data and information between networked devices for the purposes of screening the health data of a visitor at the door of a system user; computer software and software applications for mobile phones, tablets, and desktop computers, namely, software for use in monitoring home security systems, for controlling home devices and systems, for use in electronic storage of data, and for health data screening using networked devices; software and software applications permitting users to identify and communicate with persons at their door; electronic video surveillance products of security systems