Hand TerminalThe hand terminal is the universal personal smart device. This device is used for person-to-person recorded video messages and live video calls. It also operates as a personal data manager, a remote control device, and an access control key among other purposes.
It is depicted as a solid clear rectangular device which resembles the dimensions of a smartphone from the early 21st century, however, is made entirely of a glass silicate or a transparent hard glossy plastic/polycarbonate material. The display, user experience, and operating system include touch, proximal motion, and gesture detection, as well as potentially holographic projection (this may be from nearby devices that communicate in real-time with the hand terminal).
It can operate wirelessly on a cloud or on a private local communication network. Communication protocols and security protocols on the devices and the networks are unobtrusive. From the portrayal in the TV show as well as various situations throughout the books, the device is largely unusable without network connectivity.