How WURFL Works

The Problem: Device Fragmentation

Developers face the daunting problem of device fragmentation when planning, designing, and analyzing the mobile web experience. There are literally thousands of devices in use today. There are over 45,000 different device profiles in the world today, with various permutations of device, screen size, and a number of other significant capabilities. And contrary to some expert opinions voiced a few years, the problem is getting worse. Not only is the number of devices increasing, but the types of devices are also increasing, with tablets, smart TVs and gaming consoles entering into the problem.

The Solution: WURFL Device Detection

Developers across a range of industries need a fast way to identify the devices with which users access their sites and services.

To do this, the WURFL API reads the header of the HTTP request generated by the device’s client and extracts the User Agent string. Next, the WURFL API uses a finely-tuned matching algorithm to identify the device and extract its “capabilities” (e.g. device model, browser, OS, screen width, etc.) from a data source (the WURFL XML file). With these device capabilities results, a developer can write code that will optimize the mobile experience in several ways.

For example, a developer can write code that will optimize the mobile experience in several ways. For example, a developer can detect a device’s screen size. With this knowledge, the server will then serve picture or advertisement with the right dimensions to avoid that images are too large, too small, cropped incorrectly or simply take too much time to download. These are all aspects of mobile development which can significantly detract from the overall usability of a mobile site or application.

But that’s not all. Developers know that delivering a mobile application to multiple devices typically requires adjusting of HTML/XHTML mark-up, CSS and JavaScript. Similarly, no single combination of audio/video codecs and containers will work on all devices (not to mention frame-rates and bit-rates). For all these reasons, WURFL is required.

“Whats a WURFL?” – The Wireless Universal Resource File

WURFL is the industry standard for device detection and intelligence. Leading internet companies like Facebook and Google use WURFL to drive their mobile optimization, advertising, device analytics. Our WURFL Device Description Repository (an API and xml file) provides accuracy and speed developed over 15 years, containing over 45,000 device profiles.  These APIs are ideal for companies that wish to closely integrate with their own applications.  We also offer Cloud-based products that leverage the same technology, provide an always-updated DDR, and provide extra benefits like iPhone/iPad detection and an Image Resizing CDN.