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Open the YouTube app on your iPhone
Start playing the video
Press the Home button or swipe up to go to the Home Screen
Open Control Center
Tap Play to resume audio in the background
Use Picture-in-Picture if available
Open YouTube in Safari
Request Desktop Website in Safari
Start the video
Switch to another app or lock the screen
Use a third-party browser that supports background playback
Keep the video in a playlist or queue for continuous audio playback