I have some friends who are playing this on iPhone and I want to introduce them to the board game. I just wanted to check which farmer scoring and 2-tile city rules were being used in the iPhone app to make sure I'm teaching them the same rules.
2-tile cities, or "football cities" are worth 4pts each (2pts per tile)
Farm scoring is done by field. In other words, you check each field, and whichever player has the most farmers has majority control of each field. That player will score 3pts per completed city that the farmer feeds
Review of the iPhone OS version here if you're interested....