If you see something on the Amazon Fire tablet that you want to capture an image of, you can easily take a screenshot.
Press the Power and Volume down buttons simultaneously for a second or two until you see the animation on the screen. You might also hear the camera shutter sound if the tablet is not on silent.
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The Fire tablet screenshot will be saved to the camera roll in the ‘screenshots’ folder. You can move them out via a USB cable to your computer for editing and sharing if need be.