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Record the screen on your iPhone, iPad, or iPod touch - Apple Support

If the screen record option is not on your control panel, 

  1. Go to Settings > Control Center, then tap the Add button  next to red record icon Screen Recording.
  2. Open Control Center on your iPhone, or on your iPad.
  3. Tap the gray Record button gray record icon, then wait for the three-second countdown.
  4. Exit Control Center to record your screen.
  5. To stop recording, open Control Center, then tap the red Record button red record icon. Or tap the red status bar at the top of your screen and tap Stop.