I used to play Petville until it got boring. Now i play fantasia Kingdoms and Flutter. fantasia kingdoms was great when i first got into it, as there was so much to do. Right now there they're having some major glitches in the system and progress is slow as too many people are levelling up too fast. Flutter is boring in my opinion, but i continue to play it as a recent experiment i did on myself showed that when i played it, my blood pressure dropped and i became calmer, so i always play just before going to bed. The only annoying thing about Flutter would be that your quests are hard to do as they give you very little information, so you're flying around the rainforest for hours trying to find whatever it is you're looking for. I also play Ninja Saga, although i believe it's a rip off of naruto XD I haven't really gotten into that. Mahjonng Dimensions is another i play, but only very rarely now if someone beats my high score i just have to beat them XD
