SharePlay a PDF file when FaceTime.
Browse and turn pages together synchronously.
When having FaceTime with some friends, one person copies and pastes a PDF file into the SharePlay session.
Then everyone can synchronously browse and flip pages.
=== EULA ===:
[standard Apple Terms of Use (EULA)](https://www.apple.com/legal/internet-services/itunes/dev/stdeula/)