To play several videos one after another on an iPhone or iPod touch, you can create a playlist of all the videos that you want to watch. However, that playlist won't show on your device's list of playlists. To make it appear, simply add a music file to that playlist, and click OK when iTunes asks you "Are you sure you want to mix music and videos in the same playlist?"
By using a combined playlist like this, you will be able to view videos continuously -- and not only in landscape mode (like YouTube videos), but in portrait mode, like if you were holding a video-capable iPod.
Mac OS X Hints
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