I am cautious about using these new banking apps, not to say it isnt safe, just that I would like to see it working successfully without incident for a time before I contemplate using it myself.
My brother (who will buy anything shiny with an apple logo on it) assures me no extra software is needed for security on the iPad or Macs.
I use the Barclays ping it app to check my balance when I'm out and about. It's pretty handy. Haven't had the opportunity to try sending money on it yet.