How would you prefer to integrate with....
 

a third party system?

Our service is an upsell to your site that delivers a mobile version of your content to a users cell phone. We are trying to determine the easiest way for webmasters to integrate with our system.

Basically, after a user makes a normal subscription purchase on your site, we need the site to pass us the phone number, and a tag telling us which content to deliver.

So help me out! What way would be easiest for your sites? A link-away, where they get bounced to our site and then back? A PHP call? A SOAP/Web Service? Something totally different?

Any feedback would be appreciated.

Thanks!
Todd