Easy way to make a loop presentation with embedded video for iPhone/iPod/iPad

Requirement: Latest version of Keynote

1. Embed video file (which can be played by QuickTime player) into your Keynote presentation
2. Select File->Export, then go to QuickTime tab
3. Make sure that "Formats" is Full Quality, Large
4. Save .mov file somewhere
5. Open iTunes and D&D the .mov file into "Movies" Library
6. Select "Advanced" at the menu bar, then "Create iPod or iPhone Version" or "Create iPad or Apple TV Version"
7. Right click the converted video (now it is .m4v) and select "Get Info" then "Options" tab
8. Change "Media Kind" from "Movie" to "Music Video"
9. Sync the video with your iPhone/iPod/iPad
10. In your iPhone/iPod/iPad, the converted video is located at Music app (not Video app), now you can see loop button when you play the video!