You can backup your game data using a application called IPhone Explorer. It is free to and it works on my IPod touch and IPad and neither are 'Jail Broken'. Browse to \Apps\com.capcom.capcommobile\Library\Preferences\ (this path may be different on different devices). Copy com.capcommobile.zombiecafe.plist over to your local computer. This file contains the game state (Levels, Toxin, Money, etc…).
My IPod will often return a 'Directory Not Found'. To fix this I just unplug the USB connector and replug it in. That works about half the time. I am not entirely sure what the cause is but just keep trying and it will work.
If you would like to resume your game as of the last backup simply copy that file back into that directory.
Hope this helps.
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