Its by design. It uses animations to transition between actions that don't happen instantly. The experience is very controlled. For example, the scrolling on the browser isn't kinetic, ie: you can't scroll for long distances on and single flick in Mobile Safari like you can on the Android Browser. As far as I can tell, the browser scrolling on the stock Android apps transition pretty damn good. 3rd party applications aren't always up to the same level of quality, unfortunately.