If you take the "social" part serious frind's data is essential. When playing a game it should compare to your friends on the high score list. When using a bir

If you take the "social" part serious frind's data is essential. When playing a game it should compare to your friends on the high score list. When using a birthday calendar you want to see birthdays. Having to ask the friends for approval doesn't scale. There is the fundamental conflict between a social network platform and privacy.