Can't connect to itunes

I have a Iphone 4s and it can't connect to itunes. I tried to download an app, but it doesn't work. It shows me "can't connect to itunes". I can update apps but thats all. I've tried the location service, setting the date, signing in and off. I signed off and now I can't sign back in because it can't connect!

Same thing with me here. I tried downloading new apps, it can't, while I can still update my current apps. I even changed my password. I tried signing off, but I can't sign back in again. It seems that a lot around the globe is experiencing this problem. I hope Apple will do something about this as soon as possible.