Handheld devices refer to small, portable electronic devices that are designed to be held and operated by hand. These devices typically have a touchscreen interface and are used for various purposes such as communication, navigation, entertainment, and productivity. Examples of handheld devices include smartphones, tablets, e-readers, handheld gaming consoles, and digital cameras. Research in the field of handheld devices focuses on improving the performance, functionality, and usability of these devices. This includes developing new technologies, such as faster processors, higher resolution displays, and advanced sensors, as well as designing user interfaces that are intuitive and easy to use. Additionally, research in this area also explores the impact of handheld devices on human behavior, social interactions, and cognitive processes. Overall, research in the field of handheld devices plays a crucial role in advancing the capabilities of these devices and enhancing their usability in various applications.