I think Twitter is an installed B&N social app and if I remember correctly, social apps can be controlled in Settings. My NC is at home, so I cannot verify this. But check in Settings would be a good start.
That and AMV, and Woodwing..if there is nothing to do about it, then I am seriously upset. I used to love my Nook Color. Now there is continuous installations and apps I did not ask for.
Yes, it's very inconvenient.
IN trying to add it for people who need the apps (AMV and Woodwing for magazines, twitter for twitter people) B&N has unnecessarily added it for everyone. It should have been optional.
So with Twitter, AMV, and Woodwing we are pretty much messed up? they never isntall and they just stay there doing nothing.
I found a way to get rid of the Twitter app because I had the same 'Installing' problem you had.
1.- You need to download the Twitter app via browser from B&N. I don't think the internal one will let you
2.- You have to install it and it will fail (will corrupt the intenal one on the Nook
3.- Remove the installation (or Archive it) and it will remove both Twitter apps!
I have done this twice and it works. Sorry I can't remember the specific steps of how I managed to cheat the NC & B&N into allowing me to download a copy!
Sorry for not remembering the detail but I think this is what I did.
I am runnig Puffin Web browser on my Nook Color. I logged onto the B&N web page using the Puffin App and searched for the App "Twitter" The only one available is for Nook Tablet (not for Nook Color) and
I downloaded it and ran it. It began to install, but towards the begining is stopped and said something about not being able to continue (can't remember the specifics). I decided to archive it and the 'Twitter' App dissapeared from the 'APP' and from HOME. I tried unrchiving it and reinstalling it, but I got the same error, so I deleted it completelly. Now my Nook color is clean and there are no more 'Twitter' Apps shown!!!