I'm currently building a web application that can can track a users actions on a particular website and pop a URL if the user takes certain actions, such as: first click, responding to a question by clicking yes / no, clicking a submit button, or exiting the site.

It is important that these URLs are served to the user and are not blocked by pop-up blockers. It is my understanding that there are certain exceptions within the major internet browsers that allow pop-ups if they are served based on some user action, rather than serving an unsolicited pop?

Is this true? How do I design this web application so that it can serve these pops (and not have them blocked).