When you share a video to iMovie Theater, it's uploaded to iCloud so you can view it on Apple devices that you've signed into using your Apple ID. If you've turned on iCloud Drive on one device but not on others:
- iMovie Theater might appear empty on some devices.
- Some content might appear to be missing on some devices.
- New content that you share to iMovie Theater might not appear on every device.
Set up on your iOS device