Biosensor technologies have evolved rapidly in recent years, driven by breakthroughs in nanotechnology, biomaterials, and data analytics. As a result of these developments, highly sensitive, selective, and miniaturized biosensors that can identify a variety of biological and chemical targets have been designed. Emerging designs integrate novel materials, such as graphene, quantum dots, and molecularly imprinted polymers, enhancing performance in terms of speed, accuracy, and portability. Furthermore, the fusion of biosensors with the Internet of Things (IoT), artificial intelligence (AI) platforms, and wearable technologies has expanded their functionality, enabling real time, remote monitoring, and personalized diagnostics. Prospective applications are vast, spanning early disease detection, continuous health monitoring, environmental hazard assessment, food quality control, and even biosecurity. This chapter explores the latest innovations in biosensor technology, highlights their transformative potential across diverse sectors, and outlines future directions to overcome current limitations, opening the path to more easily accessible, efficient, and sustainable sensing solutions.