As regards the pinch-to-zoom, all I can think now is to add two thumb-sized transparent buttons (one in the down-right angle, the other on the down-left). They could be used to zoom in and out (calling the same function I created for "change size").
As regards the scroll speed....it is something I always thought about. But I don't know how to increase it.
I didn't changed the scroll speed: when you scroll down with the transparent bar in landscape mode, it merely call a function that scrolls down the page:
Code:
self.scrollBy(200, 0)
"Frecce" are arrows that show up when you increase the size of the image and you double tap on the screen...They scroll in 4 direction, but, again, they don't change the speed!