The bag has two inside slots for business cards, bank cards, etc. It is closed with a magnetic catch. The influence of magnets on an inserted in the envelope Bank card I have not tested. But the application of the closure and the magnet should not be a problem here.
In previous reviews it is described that it was awkward to make calls when the iPhone is in the shell or the cover of the envelope can be folded down hard. I can not confirm that. Sure, the iPhone is not as thin as before and is a bit clunky in hand but the phone so has given me no problems.
Who owns an iPhone dock should remember that the phone for syncing and charging must be taken out of the bag because it does not fit into the dock with pocket. I have solved the where I have a plastic letter opener on my desk. Thus the device can be easily detached from the bag and the iPhone will not scratch. The sync cable can be, however, even in your pocket insert.
Conclusion: All in all, a great bag that I can recommend you.