I program in the ability to dynamically move elements of your web site around on the screen so that dimensions, positioning of elements on the page, and font sizes all change according to the size of screen they are viewed on.
It’s more work than a static site, but it is a cheaper option than paying for a separate mobile version of your web site, or an app. The variety of devices available to view web pages is increasing all the time, and so making a web site responsive is the only way to future proof it.
Desktop users try dragging your browser window to make it smaller and you will see what happens the content on this web site. It should still be clearly legible right down to smart phone portrait size (320 pixels wide).