You can download the latest Android Software Development Kit directly using the links below. If you’re having trouble installing, try looking at the Installation Guide. You also may want to check out the System and Software Requirements before you attempt an installation.

Download Links (Most Recent SDK Build):

Windows Installer - (android-sdk_m5-rc15_windows.zip) - 79MB
Mac OSX Installer (Intel) - (android-sdk_m5-rc15_mac-x86.zip) - 79MB
Linux Installer (I386) - (android-sdk_m5-rc15_linux-x86.zip) - 79MB

If you use Eclipse, you may want to download the Eclipse Plugin for Android.

Upgrade Instructions Here