Gangdie is a sub-culture of indie and gangster. It combines the two and gives reference to a particular group of people who dress in a "new" gangster way.
Gangdie also breaks free from the normal mould of "gangsters" listening to "gangster" music or "rap", instead allowing them to listen to music such as Taylor Swift or other Country Music.
Dude! That kid is so gangdie! Check out all the Taylor Swift in his iTunes collection!