Facebook: How to Find Out Who Unfriended You

Third-party app lets users find out who cut them from their friends list.

— -- First comes the sting of being unfriended on Facebook and then the curiosity of who did it. Or perhaps you look up an old friend only to find they're no longer one of your social media pals.

A new third-party app called "Who Deleted Me on Facebook" promises to keep track of your friends list and notify you when a connection deactivates their account or unfriends you.

The free app for iOS and Android works by keeping track of a user's friend list from the time they download it and compares that version to future updates to account for any missing friends -- and new ones who are added.

If you're so inclined to micro-manage your Facebook friends list, you can also go about it the old-fashioned way by downloading your data and then again at a later time, allowing you to conduct a manual comparison of your contacts.