This feature is half baked. I have ios11 beta on phone and the invert isn't ready for prime time. My frustration is this has been available on Android forever and I don't know why Apple acts like it's this hard thing to implement. Same thing why don't they add numbers on top of keyboard?!?!? What do I know....I own everything Apple and these things that I would love and use daily are not really given much effort. Yes they spit out other cool things, but bread and butter should come first!