BlueStacks allows users to run Android OS apps on Windows PCs with instant switching between the two.

Features of BlueStacks

Play Android apps fast and full-screen
Push your favorite apps from your Android phone to your PC using BlueStacks Cloud Connect
Run 10 pre-loaded apps “out of the box”
Install up to 26 more of your favorite apps
May not work fast on older netbooks and tablets
Available now for Win7, and it’s Free

Download
http://cdn.bluestacks.com/public/2002/BlueStacks_AppPlayer_Alpha.msi