While before, plus WhatsApp application was needed to stop the automatic download of pictures, videos and audio files, but now, WhatsApp has added this option to your configuration. Thus, you can control the file download automatic means.
Simply go to Settings -> Chat Settings -> Technical self-discharge -> Check appropriate option "By using mobile data ',' When connected 'Wi-Fi' and 'roaming'.
That's it. Now, let's move to the next point of this article WhatsApp Tricks