I think one reason why the autocorrect in iOS is so frustrating is that, not only is it aggressive in thinking that it knows the right word, but that it doesn’t take attributes like capitalisation as hints of the word I’m trying to use.
I’ve been trying to write a post with the word “blame”, but I’ve been misspelling it as “blaim”. The iPad, trying to be helpful, is automatically changing it to “Blair”. It knows that “blame” is a possible correction — if I were to undo the change and bring up the chip of suggested alternatives, “blame” is one of them — but I never get the opportunity to select it as it changes the word from under me.
When there’s no suggestion, the misspelt word is simply highlighted. Maybe that should be the way to go for all missspellings unless iOS is almost certain that it knows the correction. I know it’s a hard problem, but it would be appreciated if more work is spent on making this less frustrating.