A researcher in University of Washington in Seattle has developed a phone that can be used to talk and text even without a battery. Backscatter, a technology which enables devices to communicate by reflecting incoming radio waves have been innovated which works on analog signals. There is a base station which transmits power to the device within a range of 15 meters. The device comes in a small LED display and one cannot talk and listen at a time. The technology is at its primary stage and considering that it is much cheaper than a normal phone; people will not have to worry about carrying power banks in the near future. Read more at: https://www.wired.com/story/this-cell-phone-can-make-calls-even-without-a-battery/