The increase in global life expectancy has led to a growing elderly population, creating an urgent need for efficient, long-term healthcare solutions. Significant advancements in material sciences and fabrication technologies, along with progress in low-power, high-speed electronics, computing, and communications, have enabled the development of high-performance, small-scale biomedical devices. These devices, including wearable, implantable, and ingestible systems, facilitate continuous monitoring of physiological parameters and support closed-loop therapeutic interventions through the integration of the Internet of Things (IoT), artificial intelligence, and data analytics. However, design considerations, such as size, safety, biocompatibility, and user comfort, must be carefully addressed, particularly for long-term monitoring applications. Furthermore, ensuring reliable, secure, and energy-efficient operation, while addressing scalability and integration complexities owing to their compact form factors, is crucial for widespread adoption. With advances in flexible electronics, material sciences, and ultra-low-power computing and communication systems, these miniaturized biomedical devices have the potential to transform healthcare delivery.