Hello everybody,
this is a small idea but may improve some thing. when I'm on clash, I want to know when some of my friends are on too... so what I'm suggesting is that for gamecenter friends and/or facebook friend that there would be a green or colored dot or something to notify you when they are online.
hope this could help!
-gunrule
The whole telling if someone is online idea has already been ruled out by SC. Takes away from the "privacy" of the game even if they are your friends on your gc.