open source mobile designing

Android Architecture

The following diagram shows the major components of the Android operating system. Each section is described in more detail below.

Application Framework

Developers have full access to the same framework APIs used by the core applications. The application architecture is designed to simplify the reuse of components; any application can publish its capabilities and any other application may then make use of those capabilities (subject to security constraints enforced by the framework). This same mechanism allows components to be replaced by the user.

For more Details : http://developer.android.com/index.html