Question

I know there are ways to detect browsers based on CSS rules but I don’t know if the same tricks would work for Outlook. The way I think it could work is have CSS rules that show and hide urls so that when a recipient clicks on a link I can tell which email program it came from.

Answer 1

I can’t see how this would be possible. Browser detection is done via Javascript (not CSS). And if the user is using a non-web-based email client (such as Outlook), clicking on a link will trigger the default browser to open and load the link. The information the browser sends to your server will have no knowledge of what application caused the browser to launch.

I think your only option would be to have different links for each client and rely on the goodness of the users to click the correct link.

I also think you’d have a fairly high success rate of guessing the client based on a few factors that ARE available after the link is clicked such as:

• The device type
• The Browser
• The Operating System
• The email address (if it’s gmail.com or hotmail.com you know 99% of them used the web client – or for a better match mix it with the device type)

Then you could make generalisations such as:

• Accessed from Windows and not a gmail/hotmail/yahoo webmail address – probably used Outlook
• Accessed from OSX and not webmail address – probably used Mail
• Accessed from either and a webmail address – probably used Browser

Rules like that could probably give you some pretty meaningful statistics.