The USP: Hook up with the people you walk past on the street.
Pros: Once you get over the slight stalker complex Happn instils on you by showing women who walked past your front door an hour ago, matching with users within a 250 meter radius is actually quite handy.
As a result there is now no end of apps with the same aim of helping you fall in love (or at the very least get lucky).
The USP: Gives you the chance to tell your friends (rather than strangers) that you want to sleep with them.
Isn't the whole point of internet dating that you can meet someone new?