It’s 2012, and Unicode is everywhere — including in iOS’s own software keyboard. (Tap and hold on e.g. the normal apostrophe to be able to select typographer’s single quotes.) Why should contractions expand into ugly, 1995-era ASCII representations?
Apple itself, for example, wouldn’t use an ASCII apostrophe in its own marketing content; for example, there are a number of apostrophes on apple.com/ipad, all of which are “educated.”
I submitted a feature request to Apple (rdar bug ID: #11156286) proposing that they at least add such an option to their General › Keyboard options.
If you agree, please “dupe” #11156286, as this counts as a vote in Apple’s system. https://bugreport.apple.com/
Thanks!