Currently, iOS autocorrect on iPhone and iPad can be somewhat of a wild beast you can struggle to keep under control – for every actual error it removes, it can feel like it also nixes loads of slang words and intentional non-standard spellings.
That may change, though, as Apple has just been granted a patent for its self-correcting intelligence. As identified by PhoneArena, it was filed in 2017 and recently approved by the USPTO.
This patent describes changes to how auto-correction works. Basically, this patent describes how auto-correction will only perform the part that misspells, rather than completely altering a spelling that is similar and correctly spelled.