What is Qwitter?
Qwitter is the popular Internet service that informs Twitter members via email when another Twitter member has stopped following them.
How does it work?
Qwitter compares your followers on a weekly basis. Qwitter will then send you weekly email notifications when anyone unfollowed you on Twitter.
How do I signup?
To sign up for the service, authorize the Qwitter app via Twitter. You do this by clicking the signup link on the homepage.