Windows :
Android Components:
- JDK 1.6: http://download.xamarin.com/Installer/MonoForAndroid/jdk-6u39-windows-i586.exe
- Android SDK: http://dl.google.com/android/installer_r21-windows.exe
- GTK#: http://download.xamarin.com/Installer/gtk-sharp-2.12.20.msi
- Xamarin Studio: http://download.xamarin.com/studio/Windows/XamarinStudio-4.0.msi
- Xamarin.Android for Visual Studio and Xamarin Studio:http://download.xamarin.com/MonoforAndroid/Windows/mono-android-4.6.00049.msi
Xamarin.iOS for Visual Studio: http://download.xamarin.com/MonoTouchforVisualStudio/Windows/mtvs-1.0.897.0.msi
You can skip steps 3 and 4 if you don’t need/want to use Xamarin Studio and use VisualStudio (2010/2012 Professional or better) instead. In that case you must have VS installed before proceeding with step 5.
OSX :
Mono Framework: http://download.xamarin.com/MonoFrameworkMDK/Macx86/MonoFramework-MDK-2.10.11.macos10.xamarin.x86.dmg
Android SDK: http://dl.google.com/android/android-sdk_r21-macosx.zip
Xamarin Studio: http://download.xamarin.com/studio/Mac/XamarinStudio-4.0.dmg
Xamarin.Android: http://download.xamarin.com/MonoforAndroid/Mac/mono-android-4.6.0-49.pkg
Xamarin.iOS: http://download.xamarin.com/MonoTouch/Mac/monotouch-6.2.0.65.pkg