no one, I don't believe it would be quite the same thing, certainly not the same level at least. Someone else mentioned Similar before about how bad it would be if say "Cessna" decided to be the major sponsor and didn't allow any other Aircraft, this would be a killer for what is essentially an Airshow, I agree, BUT, Having only a single EFB provider represented there, IMHO, isn't a death knell and would sway only a very tiny percentage of people considering going.
If it's about getting it going at all and angering a very tiny minority as a result but having an actual Airshow, then it sounds like a no brainer.