iphone

1. Connect your iPhone or iPad to you Mac 2. Open Quick Time Player 3. From the File menu, Choose new Movie recording 4. Fromt the drop down next to the record button choose you iphone/ipad for video and microphone 5. Click record 6. Do steps 7. Click Stop 8. File | Save 9. Add name, click Save 10. Close quick time player 11. Open imovie 12. From the File menu, choose new app preview
you may have to go back to the projects screen first 13. If you get the app previews info screen click OK 14. Drag and drop your recording from steps 1-9 into the bottom half of the iMovies window 15.

https://support.apple.com/en-us/HT204095 Itunes,apple

from The Iphone Blog