What do you do if your friend invites you to play a game of scrabble or poker, tries to send you a zombie, or some other invite that requires you to download an application? Should you download it even though you don't want to. What's the etiquette? Edit this page and add your thoughts.
You don't need to accept it. Most applications just ask people to send invites; they don't care if you accept it.
Chances are they will have sent the invite to loads of people and will never notice if you don't accept. If you are inundated with invited from a certain person, just block the app.