Different scales for different width/devices?

No way with that plugin, sorry.

Are there any other possibilities to do that? Like having it in a media queries or something.

Edit: I tried to scale different sizes in different media queries but no avail. So I was wondering if I did wrong anywhere.

Media Queries are the right way to get different layouts in different devices. Take a look at these code snippets.

Is there something I can do to force to scale my site to the desirable size?

This is what I got for now in my style.css:

@media only screen and (max-width: 414px) {

	@viewport {
		max-width: 400px !important;
	} 

}

‘max-width’ is not a property of the viewport. Do you mean ‘width’ instead? More about @viewport.