For those using the latest iOS5 operating system for iPhones, iPads and iPods, try the Speak Selection tool in the accessibility area. The pathway is Settings/General/Accessibility/Speak Selection, once this feature is turned on it can speak text on applications that allow you to copy text, e.g. information on web pages. Make sure you slow the speed of the text to speech down, as it speaks very fast.
Once turned on, hold your finger on the text you want read, adjust the active copy box if necessary by dragging out the edges of the highlighted area, you will then have a choice of Copy or Speak, tap speak and hear the text.
Its been a hit with the students and people I have shown and is easier than the voice over for some students.
There are a few new accessibility features for those with different learning difficulties, have a play and see if they suit any of your students or family members.
There is also a voice over tool in that section, that some of my students find a little harder to use, but works over different kinds of text. This link gives instruction in how to use the voice over http://www.apple.com/voiceover/info/guide/_1128.html