(In case I haven't already said so, welcome to the forum!)
I'm fairly certain that it's not possible to move the scroll bar to the left side. :Even if it was, I would think that'd be on an app by app basis, rather than a setting for the phone itself.
Is this your first smartphone/did you only recently get the S4? There is a little bit of a learning curve sometimes with new devices.
I and others have had issues with a feature of the Note 4 that allows you to shrink screens of apps that allow it for multi-tasking. Swiping the notification bar down just right sometimes triggers this when not intended, but with a little reprogramming of the muscle memory of the thumb, it's not an issue anymore.
Thanks for the reply. I've had the S4 since it came out. I just don't ever seem to avoid hitting the scroll bar when I'm flipping through an article or Tumbr or Facebook. Is there an app for reprogramming muscle memory?