On my 12.9 new IPP, tap the .?123 button, then long hold the ? or ! key—upside down ¿¡
Yes, I'm on iOS 11. It works as I described.
With the US English keyboard on an iPhone 6S, I get the ¿ by long pressing the ? key and the ¡ by long pressing the ! key. It's not limited to iPad Pro at all.Interesting. I assume based on this that it is now an iPad pro feature and not available for other devices. If I press ?123 and then long hold ! I get ' and with ? I get "