Smartphone-based technology is a research area that focuses on developing and utilizing mobile applications, sensors, and other capabilities of smartphones for a variety of purposes. This technology is often used in fields such as healthcare, education, and communication to improve accessibility, efficiency, and convenience for users. Researchers in this area explore ways to leverage smartphones to collect data, monitor behavior, deliver interventions, and enhance user experiences. Additionally, smartphone-based technology is often utilized for research purposes, such as conducting surveys or experiments through mobile apps. Overall, this research area aims to harness the power and ubiquity of smartphones to address various societal challenges and enhance everyday activities.