Ripped Off by EA!
You really should sync your game before quitting by visiting a friends town. So many people make threads like this and it all comes down to not syncing. It is poor design, I admit.
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This is the first time that it (knowingly) happened to me. The Android version has an option to quit, but the iOS one does not; something that should be changed in a future update. You'd think that EA would learn, but clearly they don't care.
