Recent advances in miniaturized sensing devices have led to the design of integrated analytical devices such as biosensors and sensors. Nowadays, miniaturized sensors are highly desired for real-time and fast-response measurements in clinical diagnostics. This chapter discusses different categories of lab-on-a-chip devices based on the application types for clinical diagnostics, integrated bioanalysis, environmental monitoring, and quality control as well as point-of-care applications. Additionally, this chapter focuses on recent advances in lab-on-a-chip devices in the different areas of integrated biological assays.