Is it possible to use iPad gen2/3 to stream movies to an HDTV on a cruise ship using Apple TV and my own Airport Express plugged into the proper electrical outlets? I.e a wi-fi network set up without outside wi-fi connectivity??
Yup, it is possible.
Just play the video on the iPad and then tap the AirPlay icon to choose the TV.
See this for more info -> Apple TV: How to use AirPlay Mirroring
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