by Ponton
You do not have the expansion cards or promo cards in the iOS version. So, unless you do not want to have a greater variety of special buildings (more than 80 instead of just 36), you do not need a physical copy. Of course, there is a little chance that they may add these to the iOS version of the game, but I guess the amount of work vs the potential benefit ratio is quite off towards the work part, so I doubt it will happen.(Disclaimer: In no way am I speaking from an official point of view.)