TotalReader Pro is a digital reader for iPhones and iPads. It costs $4.99, but it was free the day I downloaded it. It reads books and documents in all the common formats, such as .docx, .epub, .rtf., .doc, .ppt., .pptx, and many more. I have tried it and it works well, better than the other e Readers I have on my iPad. You can read about it here:
The Voice Dream Reader is supposed to convert text to speech and read it aloud in a natural pleasing voice, not one that mimics Darth Vader. You can download the free Lite version or the full version for $9.99 at the Apple App store.
Subtext allows teachers to embed questions, polls, discussion prompts, videos, and web links in digital text.