5. Treasure Isle
Treasure Isle is a game about collecting stuff, and it involves traveling to various different islands on search of buried treasure. Every player starts out with an avatar much like the one you get in FarmVille, an island, a hut, a n upgradable treasure chest, and a gem tree you can harvest each day. As you log in each day, you can upgrade your island, your hit, and your treasure chest with new goodies.
The game's social aspect comes into play with "neighbors", who are basically people on your friends list whose islands are adjacent to your own. You can visit your neighbors and collect stuff from their treasure chest, or even help them with their own quests.
Finally, your home island provides you with a variety of things to do–in the form of treasure hunting. You can acquire maps, tools and a backpack to find buried loot.