The presently disclosed subject matter can include or consist of the creation and manufacture of electrochromic thin film transistors, either self-sustaining or not, with lateral or vertical structure, deposited on any kind of functionalized substrate, referred to as electrochromic substrate, or non-functionalized substrate. The electrolyte material and the presence or not of an ultra-thin membrane can act as dielectric element. The electrochromic material can act as active semiconductor of the channel region. The gate, source and drain electrodes can be based on metal materials, such as Titanium, Gold, Aluminum, or degenerate semiconductive oxides, like Indium and Zinc oxide, Gallium-doped Zinc oxide. The device operation control process can be made by means of electronic and ionic current, and the off-state to on-state switch, or vice-versa, can be followed by a change of color of the device.