Needs global settings
The big issue with this one is there’s no standard font size, so one book might open with fonts at 4pt and the next might be at 20pt. I ruins the app. I haven’t seen this issue on other ebook apps. The buttons to make the font larger or smaller are both relative and global, so there’s no way (that I’ve found) to have the app display books according to pre-set preferences.
Another issue, which is common with ebook apps, is that is displays hyperlinked text in dark blue, which makes it hard to read in dark mode. It should have a option to format hyperlinked text normally, or with a user-set format. Importantly, it works on older iOS devices.
Lastly I think the page slide animation is harsh compared to competing apps. I think this could use some attention.
Despite those complaints this is my epub reader of choice.