Friendly :)G 15

This requires a facebook account. You need to link the game to your facebook account, and have 25 facebook friends who have played the game. You don't actually need to invite anyone, nor do they have to be playing at the same time or anything. Once you have 25 people, the achievement will pop in game. You can see how many you already have by clicking on "Invite Friends" at the bottom of the screen. This will show you all of your facebook friends who've played the game, and you can also send them gifts from here as well.