All app’s and websites these days need to work for several devices including desktop, tablets and mobiles. It’s not always simple detecting the type of device being used and it can sometimes be tedious adding support to your app for something which seems very simple.

Does your chosen platform not have a pre-defined way of detecting a mobile browser? Check out Detect Mobile Browsers, has several copy / paste examples for several programming languages.

http://detectmobilebrowsers.com/

Remember Apache, IIS and nginx detection examples also present for doing for pesky redirects.