Agricola is one of the all time great board games and great iPad games as well.  I write sometimes about do-something-ability and Agricola has the most:  You build a farm, complete with a home, a family, pastures and stables for animals, and you plow fields and sow them with grains and vegetables.  It’s all good clean fun but also a highly strategic and very competitive game with GenCon tournaments and ELO ratings online and such.  Roman, Docmogs and Timmerb all play online with their iPhones or iPads.