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Smart color‐changing fibers attract much attention owing to their importance as a component of flexible electronics. A facile and scalable method of multicolor reversible electro–thermochromic Ag nanoparticles/reduced graphene oxide/polyurethane conductive fiber (ETC AgNPs/rGO/PU conductive fiber) is fabricated, which contains the polyurethane (PU) as the inner layer, reduced graphene oxide (rGO) with Ag nanoparticles (AgNPs) as the conductive layer, and thermochromic paste as the outermost layer. It possesses excellent electrothermal and color‐changing properties and rapidly generates Joule heat at 0.5 V, which makes the fiber surface temperature reach 39.81 °C rapidly. The color switching rate is fast and changes from green to yellow within 2 s. During the process of 250 times on/off voltage, ETC AgNPs/rGO/PU conductive fibers still maintain excellent electrical and thermal properties and color change stability; even in the washing, strong acid, and strong alkali environment, they still have excellent durability. This human subjective adjustable electrical–thermal–color multi‐level induced modulation makes it possible to be applied to smart wearable fields such as visual camouflage, personal thermal management, and active information transfer. [ABSTRACT FROM AUTHOR]

Due to its porous structure and good elasticity, conductive polyurethane (PU) sponge is used as the main substrate of the flexible piezoresistive pressure sensor. The effective combination of conductive PU sponge and electrode material is the foundation for the pressure sensor, but it needs to be bonded by expensive conductive silver paste or copper paste. In addition, the common electrode materials weaken the flexibility of the PU sponge pressure sensors because of their rigidity. Herein, PU sponge and polyester (PET) fabric are first bonded to produce (PET‐PU) composite, which is then impregnated with graphene oxide (GO). The obtained reduced graphene oxide(rGO)@PET fabric and rGO@PU are used as electrode and piezoresistive material, respectively. Then rGO@(PET‐PU) composite is assembled into a pressure sensor only by using wire connections in the rGO@PET fabric. Benefiting from excellent piezoresistive behavior, rGO@(PET‐TPU) pressure sensor displays high sensitivity (0.255 kPa−1 at below 2.6 kPa), wide detection limit (≈0–85.0%), and long durability (over 1800 cycles). Besides, the pressure sensor demonstrates good performance in monitoring human activities, including finger bending, clicking keyboard, breathing, elbow bending, and walking posture, thus providing a promising material for human activity monitoring. [ABSTRACT FROM AUTHOR]