Boox Color Series User Manual page 38

When the page is zoomed in, the Floating Toolbar would automatically
expand proportionally in order to manage the zoomed-in page better.
Under zooming status, singe tap on the screen is set for turning
sub-pages of each page( each original page will require several time
page-turns to be completed). But tapping the virtue page-turn buttons on
the Floating Toolbar is set for turning the whole original page.