Helix-enabled advanced fibrous devices are emerging as a powerful multidisciplinary platform for next-generation soft systems, enabling robust functionality under complex mechanical and environmental conditions. Compared with conventional straight-fiber or planar architectures, helical geometries offer high mechanical compliance, large elastic deformability, and geometry-amplified responses. Meanwhile, their hierarchical pore networks and enlarged specific surface area provide additional leverage for regulating mass/heat/electromagnetic transport. In this review, we systematically summarize state-of-the-art progress in helix-enabled fibrous devices across multiple length scales, spanning one-dimensional (1D) helical fibers, two-dimensional (2D) helical fibrous membranes, and three-dimensional (3D) fluffy assemblies. We first clarify helix-formation mechanisms, structure design principles, and representative fabrication strategies, and then highlight broad applications in soft sensing, actuation, energy management, filtration and separation, thermal management, and microwave absorption. Finally, we outline key challenges and opportunities, emphasizing sustainable material platforms, programmable structural control and scalable manufacturing, quantitative structure-property relationships, real-world reliability, and coherent multifunctional integration, aiming to guide the rational design and translation of next-generation helix-enabled fibrous technologies.