What I have in mind is something that highlights Hangul characters, and reads the highlighted characters aloud (possibly at a user-chosen speed, or possibly only when the user clicks on the syllable or word). Romanization is not necessary. To me, it seems like this would be a good way to get up to speed on reading Hangul text with some added help when necessary. If anyone is familiar with a Kindle reader, the idea is likely similar to this.
I don't really mind if the source text to be used is chosen by the user (more flexible) or chosen by the software and content creator (likely higher quality audio and overall user experience). Both would be great!
Exact matches to the above are not required, but I think anything that comes close to meeting most of the requirements would qualify as an answer, as it could help in learning Hangul by "reading".
I looked over What is a good online resource or app (Android,PC) to start learning Korean from the very beginning? but nothing jumped out at me (maybe I missed something), and the answers in Websites or software showing pronunciation guide of a phrase or sentence were not very friendly towards reading longer documents or did not have text-to-speech capabilities built in.