Overview android components

App components are the essential building blocks of an Android app. Each component is an entry point through which the system or a user can enter your app.

Each type serves a distinct purpose and has a distinct lifecycle that defines how the component is created and destroyed.

Most components must be specified in the AndroidManifest.xmlfile.

component class description
Activity Component of application. It represents a single screen with a user interface.
Service Component of application, that is used to perform task in background like playing music.
BroadcastReciever Component of application, that allows to recieve events from other components of appliction, system and components of other applications.
ContentProvider Component of application, that allows to share app data with other applications. Data can be stored in the file system, in a SQLite database, on the web, or on any other persistent storage location that your app can access.