Polyconjugated and electroactive materials are, when used for electrochemical devices, soft, wet and complex materials. Polymeric chains, water and inorganic ions are the main constituents, mimicking the composition of those organs constituents of the living creatures. During reverse electrochemical reactions, those electroactive polymers change, under control of the consumed charge: volume, color, stored charge, composition, porosity, etc. Those changes allow the design of devices such as artificial muscles, smart skins, electric organs, nervous interfaces, smart medical dosage, smart membranes, all of them working under electrochemical control. This multifunctionality will be reviewed.