Of course they bought a ton of 5 star reviews. That's how major mobile platform publishers work. Once a game amasses too many 1 star reviews to cancel out your 5 star reviews, they pull it and release the game again with a new gameid but the same name.
I got burned by this once already, with SimCity. I figured it would translate quite well to a tappy phone interface, but the application was horribly broken (several of the features didn't work at all--like bridges or the economy) and then it disappeared from the app store only to re-emerge later with suddenly a huge number of 5 star reviews. I only went looking because I was trying to figure out why my version wasn't updating anymore, and discovered what EA did.
Needless to say, I will never buy an EA mobile game ever again.