An app (application) is a way to access or add information easily on a web site, blog, or desktop. Apps usually come in ready-to-use formats and can be used to do everything from posting pictures, to creating calendars, to building lists, or even to check the weather. Widgets enable users to add appointments to calendars, search for books, or to just keep a basic to-do list.
Apps are usually created by third parties, though they can be home-made. Adding apps is easy. Most require a mere click of a button. Then you can identify the site where you want to add the app, or you can copy the app code yourself then paste wherever you like. Examples of apps include: