Hydrogel‐Based Functional Materials: Classifications, Properties, and Applications

ABSTRACT Hydrogel‐based conductive materials have garnered increasing attention in the field of smart wearable devices due to their excellent flexibility, multifunctionality, and biocompatibility. This review provides a comprehensive overview of recent advancements in the development of functional conductive hydrogels. The discussion begins with key design strategies, including the rational selection of monomer systems and conductive components that form the structural and functional basis of these materials. This is followed by an in‐depth examination of their multifunctional properties, such as mechanical toughness, autonomous self‐healing, anti‐swelling behavior, intrinsic adhesion, environmental responsiveness, and recyclability. The broad and expanding range of applications is then explored, spanning flexible wearable electronics, underwater communication, and energy‐efficient smart windows, highlighting their potential in future soft electronic systems. Finally, the remaining challenges in achieving true multifunctionality and durability are addressed, along with recommendations and perspectives to guide future research directions.