It is the Facebook app that was never going to struggle to find a user base. And the app that confirms what many suspected all along: in social networking, thoughts of contact of a more intimate kind are never far away.
Titled, with total lack of euphemism, "Bang With Friends", the app allows people to anonymously register an interest with sleeping with their Facebook contacts. If their interest is unrequited, it remains a secret. If the other party has also ticked the box to register their interest, then they are both made aware. Or, to borrow the language of the app itself, they see their "Down To Bang" button change to "Awaiting Bang" - and then, well...
The result? More than 20,000 users have signed up in just four days. And no shortage of controversy and concern followed close behind.
But for the creators - an anonymous group who have revealed, perhaps unsurprisingly, that they are Californian college-aged males - the transactions is simple: "We're just giving you closer access to the truth. It should be something you're expressive about, that you're comfortable with, and if there's a beautiful woman or a handsome man you're interested in, you shouldn't hold back."