I'll try to explain the best I can.
I am trading in my 16gb Iphone tomorrow for new Iphone. My son wants me to swap my 16gb phone for his 8gb phone before I get my new phone. We both have modern war on our phones. Can I back up both devices on a PC and then apply his back up to my old device and then my back up to his device that way I have my game when I get new device in order to transfer it to new iphone?
or
Do all I need is a funzio ID? Can I simply download modern war onto new iphone 6 and select transfer game and new device and then enter in Funzio ID?