app

noun
  1. A software application, especially one designed for a mobile device such as a smartphone or tablet. noun
    I downloaded a new fitness app to help track my workouts.
    The app crashed when I tried to open it on my phone.
  2. A program or piece of software designed to fulfill a particular purpose. noun
    The company developed an app to streamline their customer service process.
    There is an app for almost everything these days, from shopping to meditation.