Certified Messages are one-time self-destructing messages. These messages are sent as special links in chats and emails. Here is the cool part. As soon as the message is read a Certified Message link takes on a totally new functionality. It becomes a tripwire reporting on any unauthorized viewers.
Use Certified Messages to improve the privacy and security of many of your favorite web-based chat and email environments such as Google Plus, Facebook, Twitter, GMail, Hotmail, Yahoo Mail and more. You can see if anyone has been spying on you by going back and looking at the Certified Message links to see the IP addresses attempting to access your links.