Google启动了开放手机平台Android，并提供了软件开发包SDK下载。在SDK中有一款制作精良的手机模拟器。Android Emulator是一款功能非常齐全的模拟器，电话本、通话等功能都可正常使用(当然你没办法真的从这里打电话)。甚至其内置的浏览器和Google Earth/Maps(支持街道实景!)都可以联网。用户可以使用键盘输入，鼠标点击模拟器按键输入，甚至还可以使用鼠标点击、拖动屏幕进行操纵。
What is Android?
Android is a software stack for mobile devices that includes an operating system, middleware and key applications. This early look at the Android SDK provides the tools and APIs necessary to begin developing applications on the Android platform using the Java programming language.
Features
-Application framework enabling reuse and replacement of components
-Dalvik virtual machine optimized for mobile devices
-Integrated browser based on the open source WebKit engine
-Optimized graphics powered by a custom 2D graphics library; 3D graphics based on the OpenGL ES 1.0 specification (hardware acceleration optional)
-SQLite for structured data storage
-Media support for common audio, video, and still image formats (MPEG4, H.264, MP3, AAC, AMR, JPG, PNG, GIF)
-GSM Telephony (hardware dependent)
-Bluetooth, EDGE, 3G, and WiFi (hardware dependent)
-Camera, GPS, compass, and accelerometer (hardware dependent)
-Rich development environment including a device emulator, tools for debugging, memory and performance profiling, and -a plugin for the Eclipse IDE
官网：http://code.google.com/android/
Download: Android SDK For Windows
Download: Android SDK For Mac OS(仅限Intel架构)
Download: Android SDK For Linux