we are 3 students of Computer Engineering at the University of Florence and we just made our first app, named "Seen At..??".
"Seen At..??" lets you read your Facebook messages without letting the sender know about it,
that is without making the 'Seen @' message appear on their Facebook chat screen!
Everytime you receive a Facebook message notification, just open "Seen At..?" and read the message, without
letting the sender know about it!
Obviously, the app is totally FREE. Try it out!