The Android component consists of:
A compatibility definition document (compatibility definition DOCUMENT,CDD) and a Compatibility test package (compatibility test suite,cts) that describe the performance that mobile devices need to support the software stack.
A Linux operating system kernel
Open Source Library for application development, including SQLite Webkit OpenGL and a media manager
Runtime for running and hosting Android applications, including Dalvik virtual machines and core libraries that provide Android-specific features
An application framework that implicitly displays system services to the application layer, including window managers, location managers, databases, telephones, and sensors
A user interface framework for hosting and launching applications
A core set of preinstalled applications
Software development kits for developing applications, including tools, plugins, and documentation
Features of the Android SDK:
Access to hardware (including cameras, GPS, and sensors)
Data transfer using WiFi, Bluetooth technology and NFC
Maps, geocoding, and location-based services
Background services
Data storage and retrieval using the SQLite database
Shared data and inter-application communication
Enhance your home screen with widgets and live wallpaper
Wide range of media support and 2d/3d graphics
Cloud to Device Messaging (C2DM)
Optimized memory and process management
Android software Development Kit (software development KIT,SDK):
Android API SDK Core is the Android API library, it provides developers with access to the Android stack method
Development tools
Android virtual Device Manager and emulator
The complete documentation
Sample code
Online Support
Android software Stack:
Linux kernel
Library on top of the kernel, Android contains a variety of C + + core libraries
Android runtime
Application Framework
Application Layer
Android Application Architecture:
Activity Manager and Fragment Manager
Views View
Notification Manager (Notification Manager)
Content Provider (contents provider)
Resource Manager (Resource Manager)
Intent
Android 4 Advanced Programming (third edition) Android introduction