Validating an App Idea that helps people remember information they have read

Hi everyone, sharing an app idea and I'm looking for honest feedback and also if such ideas exists.

The goal of this app is to help users remember important content they have read.

How it works: Users upload a document (lecture notes, textbook, research paper, white paper), reading of the document is done on the app, so somewhat like a goodnotes system. The users can highlight keywords or phrases that are important to them or they need to remember, and also further annonate to help breakdown the keywords for better understanding.

Here's what is different:

1. Each phrase that is highlighted will be stored in a local database for each document, labelled with the page number where the highlighted text can be found. This helps the user search for these imported information easier
2. The user can optionally create an AI summary based on the context of the document and what the user has highlighted in that document. The AI summary will be turned into a voice recording that the user can listen to while commuting. This way, the AI summary will not be generic and trivial, but curated to what the user thinks is important.

Personally, this helps me create a system to remember important information from the documents I've read. I think it could value add to students, researchers, book-readers, or anyone that has to read lengthy documents for their job.

But my ego aside, what do you think of such an idea? Do you see this as an upgrade to existing productivity apps and would you use/pay for it?

Thank you for taking the time to read