Have you ever wanted to say something to a person only when they know it already? Or would you like to test how much your friends really know you?
This app will let you send a message to one of your friends, but they will not know who the sender is until they reply correctly - and is is you who specify the expected response.
The message can be as simple as "Do you want to grab a beer?". You expect a positive answer and the receiver will only know who invited them once they say "Yes".
Or you can finally get out of friend zone saying "I think Im in love with you. Write my name if you have feelings for me, too. That way we will both know...", and wait until they reply with your name.
Use your imagination. Sky is the limit!