Conformal fiber bioelectronics: Bridging flexible electronics and precision medicine

Fiber‐based bioelectronic devices have emerged as a compelling platform for wearable and implantable health technologies, owing to their one‐dimensional topology, mechanical compliance, textile integrability, and compatibility with minimally invasive deployment. This review systematically examines advances in fiber bioelectronics across four domains: physical sensing, chemical sensing, therapeutic applications, and functional upgrading of established clinical devices including sutures and catheters. For each domain, the governing material architectures, transduction mechanisms, and fabrication strategies are analyzed from conductive network design and encapsulation to coaxial spinning and in‐textile photolithography. And system‐level integration is further discussed, encompassing multimodal sensing arrays, theranostic closed‐loop platforms, and fiber‐scale sensing–computing convergence. Key performance considerations—signal stability under mechanical deformation, long‐term in vivo biocompatibility, multi‐parameter selectivity, and scalable manufacturing—are critically assessed across application contexts ranging from epidermal sweat monitoring to implantable hemodynamic and neurochemical sensing. The field is converging on system‐level reliability in complex physiological environments rather than isolated metric optimization, with functional modification of mature clinical devices offering a near‐term pathway to translation. Challenges and future directions are outlined, with emphasis on closing the gap between laboratory demonstration and clinical deployment.