A simple JS library that detects mobile devices.
Big thanks to Igor Ribeio Lima for his contributions.
I had a specific requirement for a project when I created this:
- Redirect all iPhones, iPods, Android phones, and seven inch devices to the mobile site.
A completely separate site had been created for mobile devices, so feature detection/graceful degredation/progressive enhancement were out of the question. I had to redirect.
I couldn't do detection on the back-end, because the entire site was cached and served by Akamai; I had to do the detection client-side.
So I resorted to UA sniffing.
I tried to keep the script small (currently ~740 bytes, minified) and simple, because it would need to execute in the <head>
, which is generally a bad idea, since JS blocks downloading and rendering of anything else while it parses and executes. In the case of mobile redirection, I don't mind so much, because I want to start the redirect as soon as possible, before the device has a chance to start downloading and rendering stuff. For non-mobile platforms, the script should execute fast, so the browser can quickly get back to downloading and rendering.
isMobile runs quickly on page load to detect mobile devices; it then creates a JavaScript object with the results.
The following properies of the isMobile
object will either be true
or false
isMobile.apple.phone
isMobile.apple.ipod
isMobile.apple.tablet
isMobile.apple.device
(any mobile Apple device)
isMobile.android.phone
isMobile.android.tablet
isMobile.android.device
(any mobile Android device)
isMobile.windows.phone
isMobile.windows.tablet
isMobile.windows.device
(any mobile Windows device)
isMobile.seven_inch
true
if the device is one of the following 7" devices:- Nexus 7
- Kindle Fire
- Nook Tablet 7 inch
- Galaxy Tab 7 inch
isMobile.other_blackberry_10
isMobile.other_blackberry
isMobile.other_opera
(Opera Mini)isMobile.other_firefox
isMobile.any
- any device matchedisMobile.phone
- any device in the 'phone' groups aboveisMobile.tablet
- any device in the 'tablet' groups above
I include the minified version of the script, inline, and at the top of the <head>
. Cellular connections tend to suck, so it would be wasteful overhead to open another connection, just to download <1kb of JS:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<script>
// Minified version of isMobile included in the HTML since it's <1kb
(function(i){var e=/iPhone/i,n=/iPod/i,o=/iPad/i,t=/(?=.*\bAndroid\b)(?=.*\bMobile\b)/i,r=/Android/i,d=/BlackBerry/i,s=/Opera Mini/i,a=/IEMobile/i,b=/(?=.*\bFirefox\b)(?=.*\bMobile\b)/i,h=RegExp("(?:Nexus 7|BNTV250|Kindle Fire|Silk|GT-P1000)","i"),c=function(i,e){return i.test(e)},l=function(i){var l=i||navigator.userAgent;this.apple={phone:c(e,l),ipod:c(n,l),tablet:c(o,l),device:c(e,l)||c(n,l)||c(o,l)},this.android={phone:c(t,l),tablet:!c(t,l)&&c(r,l),device:c(t,l)||c(r,l)},this.other={blackberry:c(d,l),opera:c(s,l),windows:c(a,l),firefox:c(b,l),device:c(d,l)||c(s,l)||c(a,l)||c(b,l)},this.seven_inch=c(h,l),this.any=this.apple.device||this.android.device||this.other.device||this.seven_inch},v=i.isMobile=new l;v.Class=l})(window);
// My own arbitrary use of isMobile, as an example
(function () {
var MOBILE_SITE = '/mobile/index.html', // site to redirect to
NO_REDIRECT = 'noredirect'; // cookie to prevent redirect
// I only want to redirect iPhones, Android phones and a handful of 7" devices
if (isMobile.apple.phone || isMobile.android.phone || isMobile.seven_inch) {
// Only redirect if the user didn't previously choose
// to explicitly view the full site. This is validated
// by checking if a "noredirect" cookie exists
if ( document.cookie.indexOf(NO_REDIRECT) === -1 ) {
document.location = MOBILE_SITE;
}
}
})();
</script>
</head>
<body>
<!-- imagine lots of html and content -->
</body>
</html>
#####Installation
npm install ismobilejs
#####Usage
var isMobile = require('ismobilejs');
console.log(isMobile(req.headers['user-agent']).any);