For the vast majority of Android phones and tablets, to take a screenshot you simply press and hold the power and volume-down buttons together. There is a slight knack to this action: press the power button too soon and the display will switch off; press the volume-down button too soon and your screenshot may be marred by an onscreen volume slider. After a few seconds the screen will flash and a notification will appear in the drop-down bar at the top of the screen, giving you options to delete, share or edit the image. You can also access the screenshot from your Gallery.