How do you set a custom environment variable (htaccess) based on device?

Question

How would you perform a simple mobile browser check and store the resulting boolean in an environment variable in .htaccess so that PHP can do a simple DEFINE('ISMOBILE',(env check ? true : false)); statement in a common include file?

I have seen some scripts about redirecting mobile and setting cookies, but not found (yet) the right detection and setting flow for this one.

Thanks

Answer 1

Perhaps this post can be used as a base for what you wish to do?

http://www.eldeto.com/another-apache-config-file-mobile-device-detection

This separates devices in "high-end" and "low-end", but you only need to expand the ifs in there to set more values than mh and ml

Edit: Here's an example, based on what that page has:

RewriteRule .* - [E=ismobile:false]
RewriteCond %{HTTP_USER_AGENT} ^.*(iphone|android|nokia|BlackBerry).*$ [NC]
RewriteRule .* - [E=ismobile:true]