There could be a reason why Android devices do not have built-in screenshot features. The most sensible reason is related to security. But if the iPhone and iPad have easy screenshot mechanisms, why can’t the Android have it too? Samsung devices have this built-in screenshot feature but other brands do not have it.
The solution is to download screenshot apps from the Google Play store but this usually requires rooting your device. The other solution is to download desktop apps like the MyPhoneExplorer but that limits taking screenshots on the desktop only. It’s still better if screenshots can be freely taken on the device itself.
To take a screenshot on your new Nexus 7, hold in the volume down and the power buttons at the same time. After a brief pause, you'll hear an audible noise and see an animation.
Watch the video here:
Do this for about a second or two until you see an animation of the screen zooming out. You’ll then see a notification on the notification bar saying that the screenshot has been saved. The screenshot is automatically saved in the Nexus 7’s Gallery folder under a subfolder named Screenshots.