Here are the steps for Picture-in-Picture in iOS
1. Start Lunascape App
2. Open Youtube and play the video you wish to view
3. With the video playing, click "..." in the lower right corner of the Lunascape App
4. Select "Desktop site"
5. Tap the playing screen to reduce the screen size
6. Picture-in-picture is now complete
Open the App you want to work with while doing picture-in-picture.