It is true, that using effects with viewport, means that your content, is almost always going to be scaled, and not match the native resolution. And definitely, in some cases, users are going to have to zoom, to be able to see or read anything, particularly text. Since, everything, all scaled depending on the size of the screen, fitting the current layout, precisely, into the users screen. Whether, it’s a four inch phone or a 12 inch tablet, but actually, your text in UI will not change at all on the desktop. Because, currently, at least, none mobile browsers, don’t respond to the view port at all. In some cases of course, it’s the right thing to do, if you just want to get the UI to fit on the screen, to use, fix with view port, like in my sync app, but of course those dials are awfully small, which makes the UI very hard to use.