Auto-play video can be annoying especially when you are doing something serious on your Facebook or any other social media. Agreed that your FB friends love to share good content, but not those long videos that run for more than 10 minutes.
How to Disable Auto-play Facebook Videos on iPhone/iPad
Step #1. Launch Facebook app on your iPhone.
Step #2. Tap on More menu (three horizontal lines in the bottom right corner) → Scroll down and tap on Settings.
A menu will swipe up with three options: Account Settings, News Feed Preferences and Activity Log.
Step #4. Tap on Account Settings.
You will be landed on Settings screen.
Step #5. Tap on Videos and Photos.
Step #6. Tap on Autoplay option.
Autoplay option OFF.