Some of the most important android libraries which includes application framework, interface building, graphics drawing and database access they are as follows:
android.app : This library allow to access the application model and is the basis of all Android applications.
android.content : This enables content access, publishing and messaging between apps and app components.
android.database : This Enables access to data published and include SQLite database managements classes.
android.opengl : Java interface to the OpenGL ES 3D graphics executing API.
android.os : Provides app with accesss to sandard OS services with messages, system services with messages and unter process communication.
android.text : This library is used to render and manipulate text on a device display.
android.view : This library is the central building block of application user interfaces.
android.widget : This library have a huge collection of pre-built user interface constituents such as buttons, labels, list views, layout managers, radio buttons etc.
android.webkit : This library allow us to use web-browsing capabilities in our application.
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