Just like the Kindle app, there should be a section to preview all the highlighted text on the app, this way you can make a summary out of the important pieces of the text without having to scan the whole document.

Under the comment sections it shows the user who highlighted certain part but it is useless, i want to see the text i highlighted.

Lastly, i would like to export all the highlighted pieces into a single file so I can have my summary ready to take with me, along with the comments/ annotations i write.