I bought the iPad version which I thought would work on the iphone as well. Do I have to pay another $10 for the iPhone version?

Perhaps I am missing something obvious but I backed out of a game in the middle and then tried re-entering it and could not. I got a screen allowing me to visit stats etc. At the top there was an option to "back" and another for a "new game". But try as I might I could not re-enter the game in progr...