The dreadful shooting of 2 journalists in the USA this week, and the subsequent posting of the videos showing this have prompted calls for auto-play on videos on social media to be switched off by default, rather than the current on by default setting.
It is easy to change the auto-play setting on both Facebook and Twitter accounts.
The BBC story about the issue explains how:
On the desktop view, Facebook users must go to their settings, then click "Videos" - the bottom option on the list on the left of the screen - and change the autoplay video option to "off" in the dropdown menu.
On iOS devices, users who want to disable the feature must press the three line icon, then select "Settings" and "Account Settings", before tapping on "Videos and Photos". Then they must tap on "Auto-Play" and "Never Play Videos Automatically".
Android users should begin by pressing the three line icon, then tap "App Settings", before selecting "Video Auto-play" and then turning it off.
Twiter users on desktop must go to their settings and untick the "Video autoplay" option under the "Account" tab.
On iOS, users must take the same route to their settings, then enter then video autoplay options and select "Never play videos automatically". The method is similar on Android devices. [/quote
Read more here: http://www.bbc.co.uk/news/technology-34073206