A smartphone app is a software application designed specifically for use on mobile devices, such as smartphones and tablets. These apps are typically developed to take advantage of the unique features and capabilities of these devices, including their touchscreens, GPS technology, cameras, and other sensors. Smartphone apps can provide users with a wide range of functions and services, from simple games or utilities to more complex tools for communication, productivity, or entertainment. They are typically available through app stores such as the Apple App Store or Google Play Store, where they can be downloaded and installed on individual devices.