As far as apps for textbooks go, this one is the best I’ve used; all the texts I have access too are formatted very nicely and the ability to change the font, font size, background color, etc is all great.
I have one major issue with night mode however.
On larger iPhones (I can only confirm for the 12 max), the “scrub bar” along the bottom that shows your place in the textbook stays white.
Once it disappears, it leaves a blank white box in its place. Unfortunately, that really ruins the whole point of night mode and is really distracting.
Plus, considering that one might be reading for hours it’s a serious burn-in risk for OLED devices; it is an unmoving, pure white rectangle on a contrasting dark gray background. As a result, that section will be getting magnitudes more “wear” than any other part of the screen
Ideally, that bar would totally disappear when reading since it doesn’t even show the position once it’s not active. But, it could also be fixed by just making that bar the same dark gray as Bookshelf controls. Everything else is, so it seems like an oversight.
It would also be nice if the contents, notebook, bookmarks, and flash card section were also night-mode friendly, but at least those aren’t screens you’d spend hours on like you would for the reading