Google Glass
Google Glass is an optical head-mounted display, that is designed in the shape of a pair of eyeglasses. It was developed with the mission of producing a ubiquitous computer. Google Glass displayed information in a smartphone-like hands-free format. Wearers communicated with the Internet via natural language voice commands. Google started selling a prototype of Google Glass to qualified "Glass Explorers" in the US on April 15, 2013, for a limited period for $1,500, before it became available to the public on May 15, 2014, for the same price. The headset has received massive criticism and legislative action due to privacy and safety concerns.