Generic principles

Guidelines for app design describe the core principles of the Android application framework. Few things about Activities here:

• Activities are the main building blocks of Android applications.
• As the user moves through the user interface, they start activities one after the other.
• Each activity has a life-cycle that is independent of the other activities in its application or task.
• Android keeps a linear navigation history of activities the user has visited (activity stack).
• Data can be transferred among activities using the Intent class.