Talk about snobery! I could really care less what anyone "thinks" of what I choose to do as a parent. If I choose to bring an ipad, dvd player, coloring book, etc. to the table to entertain my kids then so be it (of course it should not be noisy). If you get all hot and bothered by this (on a cruise that is geared to children - i.e.- the giant mouse) then maybe you belong on a different cruise line that caters to people of your "breeding" and "societal place".
As far as my kid having something and it being a potential distraction to your kid that is your problem. You could say the same thing about a toy, shirt, piece of jewelery-- it is endless and part of life. If my kid wants the barbie doll your kid brings to the table should I get up in a huff and leave or be offended - NO???
By the way - on our last
DCL cruise a great deal of the dining room had players, ipads, coloring books, etc. It is a great way to be able to enjoy dinner for myself and those seated around me. I have been dismayed at those parents of special needs kids making excuses as to why these devices are life savers. You don't need to tell these buffoons why you are using an ipad or DVD player. There isn't a need to draw a distinction between a special needs child and any other child.
Also, drawing a distinction between a coloring book and a player of some kind is nonsense - it is just technologies from different eras. By saying one is OK and the other is not you are showing your technological obsolesence and illiteracy.
Last, I respect your right to make a decision to leave the table because you don't like my ipad. If you do it like an ***** though we'll have words.