Speak Selection may have been the most widely appreciated accessibility feature in iOS 5. I wrote about it in November of 2011. Speak Selection reads aloud any selected text on an iPad, iPhone, or iPod Touch. Now there is the option of having each word highlighted as it is spoken. This can make it easier for the reader to track what he or she is reading.
As is the case with all accessibility features in iOS, the highlighting must be turned on. To turn it on, the user must go to:
Settings – General — Accessibility — Speak Selection