The current and main concern “Engineering Applications in Electronics” is dedicated on the applicability of thin films in different high-end applications. In this chapter, the following applications of the thin films are discussed further; it is observed that the thin films have many more applications in other semiconductor devices, display technologies, sensors, and detectors. Thin films are important in manufacturing aeroplane and other semiconductor devices since they allow for a better miniaturization and upgrading of circuits in the devices to be made. In the case of display technologies, thin films play a role in better screens like OLEDs and LCDs to enhance the resolution and energy utilization. The chapter also touches on the applications of thin films specifically in sensors and detectors due to its ability to detect even slight changes in the environment together with the biological markers. Through the review of these applications in this chapter, the emphasis is placed on the core concept of thin films which enhances the technological growth of electronic devices, promotes innovation and optimizes performance in numerous gadgets. The information gathered presents the information enumerating the significance of thin films in today’s circuit boards and display how they are absolutely crucial to engineering.