To be honest, none. I could live without any of the apps installed on my devices as there are many others that could replicate what I need with no fuss whatsoever.
I have no idea what TheScore is, but it sounds sports related so I have zero interest in it.
Of the apps that I use daily, I would say BBC News and Atomic Web Browser are my 'most used' but if either stopped working, I could still get what I wanted via other apps quite happily. In fact, I have Sky News and LA Times also for news and Chrome and Mercury browsers installed on my devices too.
I don't have the Facebook app nor the Twitter app. I use Tweetcaster instead of Twitter (rarely) and don't use Facebook at all.