Regarding the PDF viewer on Android and IPadOS.
After zooming in to a page (to fit the text to desired size), the zoom level resets after swiping to a new page or is difficult to control in continuous page transitions. This becomes annoying as the user must constantly re-zoom for each new page.
Could you implement a custom page fit that maintains the zoom view for each new page when using jump page transitions?
For continuous page transitions the zoom view should only translate in the scroll direction.