The Apple Books version wasn't just a static animation—you could partially flip the page, flip it back, make just the corner flip up a little then push it back in place, et c., all with smooth and responsive enough operation that it was close-enough to feeling like a real, physical thing. The "back" of the page, as it flipped, showed the text from the front as if it were showing through thin paper, it wasn't just blank. Lots of apps have page flip animations but most of them are both non-interactive and bad. Apple's was interactive and good. Dunno if Kindle's is as good—I used it long ago and my recollection was a slow, ugly, non-interactive page flip animation, but it may have changed since then.