The three main types of mobile applications are: 1 Native Apps: Developed for a specific platform (iOS or Android) using platform-specific languages and tools. 2 Web Apps: Accessible through a web browser and built using web technologies like HTML5, CSS, and JavaScript. They are not installed on the device but run on a web server. 3 Hybrid Apps: Combining elements of both native and web apps, hybrid apps are built using web technologies but are wrapped in a native container that allows them to be installed and accessed like native apps.