Why HTML/Web UI response slower than Native UI?

Question

I can\'t understand, Why HTML/Web UI response slower than WinForms/WPF/Android View/Native UI?

The Native UI also have styles, elements nesting, events than the CSS, DOM

Answer 1

One thing to keep in mind is that the browser itself is a native application, so anything built for the browser to run is inherently written with (at least) one additional layer of abstraction, versus something written directly for native execution.

It's also worth noting such dynamics as this:

300ms tap delay, gone away http://updates.html5rocks.com/2013/12/300ms-tap-delay-gone-away

The initial impetus for this artificial delay was to support pinch-zooming vs other touch interactions -- that is, slower responsiveness in this case was a deliberate way to disambiguate different user actions.

Granted, while this is a rather specific use-case, the general concept does serve as an example of the different considerations for browser-based vs native implementations. That is, browser-based experiences include some of the usual framework cost of solving for a wide variety of interactions and content, whereas native experiences are naturally tailored more specifically to only listen for / respond to the desired interaction models.

Throughout the implementation, many tiny parts (such as this) are slimmer and more focused in a raw native version, which can contribute to the general effect of better responsiveness.