An "Android app" or "iOS app" refers to a software application designed specifically to run on a mobile device powered by the Android operating system (developed by Google) or iOS operating system (developed by Apple), respectively, allowing users to access various features and functions on their smartphones or tablets through a user-friendly interface. Flutter is a cross-platform UI toolkit that is designed to allow code reuse across operating systems such as iOS, Android, web, and desktop, while also allowing applications to interface directly with underlying platform services
