Detector

Detector is a simple, PHP- and JavaScript-based browser- and feature-detection library that can adapt to new devices & browsers on its own without the need to pull from a central database of browser information.
Detector dynamically creates profiles using a browser's (mainly) unique user-agent string as a key. Using Modernizr it records the HTML5 & CSS3 features a requesting browser may or may not support. ua-parser-php is used to collect and record any useful information (like OS or device name) the user-agent string may contain.
With Detector a developer can serve the appropriate markup, stylesheets, and JavaScript to a requesting browser without being completely dependent on a front-end-only resource loader nor a browser-detection library being up-to-date.
Check out the README for more information as well as the full list of features.

 http://detector.dmolsen.com/