Because of the way farm-recovery is being implemented in v1.4 ("Soon!"), it will be possible for multiple copies of your farm to exist.
Because of the the way auto-save works, it will be possible to run 2 copies of your farm, make changes in both, and have one of the copies "stomp"-save over the other, costing loss of progress.
Because "safeguard" and "recover" farm is being implemented via Facebook login (soon: Google, others), anybody who can login as you on Facebook can get a copy of your farm.
My question to you is:
What's the worst that could happen?
I mean this from all angles. Obvious ones include:
* What's the worst possible cheat someone could effect using multiple copies of their farm?
Item duplication? Coin duplication? I don't think so, but maybe I'm missing something.
* What's the worst possible user experience related to multiple copies of their farm.
What comes to mind is: (a) user could purchase IAP on farm #1, then farm #2 auto-saves without IAP-information and they lose real-world cash.[1] (b) You could sign-in to Facebook on someone else's iPad, forget to sign out, they use the "already logged in" feature to "recover" your farm (putting a copy on their device), then forget about it. You spend the next month working really hard and advancing your farm, then the other person launches your month-old farm and saves it. The next time you launch, you're back to that old farm.
What else might go wrong?
What are some possible fixes?
Thanks!
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[1] There are big, giant warnings about how you shouldn't do this, baked into the system. I can't help people who willfully damage themselves.