Abstract: Electronic displays devices can present electronically changeable displayed images including graphical and textual elements, for example, human and machine-readable elements. The devices can include a low-power-consumption display that uses little or no power until a portion of the display is changed. The electronic display devices can be wirelessly connected to computing devices such as portable computing devices (e.g., smartphones, smartwatches, tablets, laptops, etc.) and fixed gateway devices (e.g., wireless access points) by a wireless communications network. The devices can include a motion sensor and functionality for determining identity, proximity, and/or location of the device.