"Responsive Javascript"

I’m currently in the process of creating my next item and came across that a responsive layout through media queries is all good but what about the javascript. For example tooltips or even hover effects aren’t needed on mobile phones. How would I pass them properly?

I already know about responsejs, but how are you doing it? Any alternatives? Is responsivejs the way to go? Any feedback would be appreciated as usual

function is_touch_device() {
  return !!('ontouchstart' in window);
}
.
.
.
if (is_touch_device()){
do something only on mobile devices
} else {
do something only on not mobile devices
}

Create a custom Modernizr script to detect touch devices,

call custom .js when touch devices are detected using that script