Add audio from a video clip in iMovie on iPad
When you add a video clip to your project, you can choose to add just the audio.
With your project open, scroll the timeline so that the playhead (the white vertical line) appears where you want to add the audio clip.
Tap Videos in the media browser.
If the media browser is not visible, tap the Add Media button in the upper-right corner, then tap Video.
Tap a category, then browse to a video clip.
Tap the clip, then do any of the following:
Preview a clip before adding it to your project: Tap the Play button .
You can also swipe left and right over a clip to manually preview the video, which can help you identify exactly which part of the clip you want to use.
Note: If you use iCloud Photos, some media may be stored in iCloud but not on your device. If a Download button appears when you tap a clip, tap the button to download the clip to your device.
Add the entire clip’s audio to your movie project: Tap the More Options button , then tap Audio Only.
Trim the clip before you add the audio: Drag the yellow trim handles to select just the portion of the clip you want to add, tap the More Options button , then tap Audio Only.