Mobile app development is the process of designing, building, and deploying applications for smartphones and tablets. It involves using technologies like Kotlin, Java (Android), Swift (iOS), or cross-platform frameworks like Flutter and React Native. Developers focus on UI/UX, performance, security, and seamless functionality. Apps can be native, hybrid, or web-based, catering to various business needs. Regular updates, testing, and optimization ensure a smooth user experience and high engagement.