It will run on iOS 4. I upgraded to an iPhone 4 so I began fresh. If
you choose the same user id, the app will let you and if you are on
the board you can see your previous rating. The app cannot tell if you
were the previous owner of the same user id. When you start fresh you
begin with a rating of 1200. You do move up fast because your skill
level will probably be better. The downside is that the server will
pick opponents close your "skill" level which is now at 1200 so you
end up playing against a lot of beginners.
I had backed up my old phone and then did a restore from a previous
backup but the ratings did not carry over. If you play Zynga poker,
your money carries over. This would indicate the money is stored on
Zynga servers and ratings on ireversi is kept on the phone.
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