A Beautiful Site

Detecting mobile devices with JavaScript

A drawing of a cartoon man pointing upwards

Heads up! This post was written in 2011, so it may contain information that is no longer accurate. I keep posts like this around for historical purposes and to prevent link rot, so please keep this in mind as you're reading.

— Cory

While I understand and value the concept of feature detection over browser detection, sometimes the need for knowing whether or not we're dealing with a mobile device arises. For in-depth device checking, you can rely on a complex library such as The MobileESP Project. But for simpler applications, the following snippet can be useful.

var isMobile = {
  Android: function() {
    return navigator.userAgent.match(/Android/i);
  },
  BlackBerry: function() {
    return navigator.userAgent.match(/BlackBerry/i);
  },
  iOS: function() {
    return navigator.userAgent.match(/iPhone|iPad|iPod/i);
  },
  Opera: function() {
    return navigator.userAgent.match(/Opera Mini/i);
  },
  Windows: function() {
    return navigator.userAgent.match(/IEMobile/i);
  },
  any: function() {
    return (
      isMobile.Android() ||
      isMobile.BlackBerry() ||
      isMobile.iOS() ||
      isMobile.Opera() ||
      isMobile.Windows()
    );
  }
};

While this doesn't account for all mobile platforms, it will pick up the most popular ones out there.

Examples #

To check to see if the user is on any of the supported mobile devices:

if (isMobile.any()) {
  alert('Mobile');
}

To check to see if the user is on a specific mobile device:

if (isMobile.iOS()) {
  alert('iOS');
}