Check if user is mobile with JavaScript.

is_mobile.js

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