Android 4.0 screenshot functionality on Galaxy Nexus
By Leo Gaggl
One of the features I missed since the good old Android 1.5 days was the ability to take screen-shots on the device. Prior to Android 4 (ICS) the only workable way to create screen-shots was to connect via USB cable and use the Android SDK to make remote screen-shots.
On Android 4.0 all you have to do is press Volume Down Key + Power Key down at the same time and hold. You should hear the camera click (if audio is on) and Android will show a notification that the screenshot was saved on your device and you can now upload or transfer to your favourite service.