We have a landing page hosted with Unbounce whereby the button on the page fires off an email to the end-user/lead. We drive traffic to this page from an iPhone/Android app.

The user may then interact with a link in this email which may fire up a different web browser than the one they viewed the Unbounce page in.

When we track our conversions (from a “Thank You For Your Order” page), we include the Unbounce tracking script.

My question is - is there a way to set a value in the DOM or URLs that is a surrogate key to uniquely identify the user that can get carried through the process so that Unbounce knows to count their conversion event despite the email detour?

My quick search did not find anything obvious…