A brief summary: It selects some Miis that you either create yourself, from the Mii Maker (and this detour also from the StreetPass Lobby or from a WiiU) may import or a QR code, this draw then in a block of flats one on the island and experience all sorts of crazy things. The whole works like a mixture of a Tamagotchi and the "Sims". You have to take care of his Miis, buy them food, clothes and home furnishings, and sometimes act as a decision-making aid when they are not sure how best to start a conversation to begin friendships or romantic relationships. But they also lead their own life, you meet them at the beach, and later in other places, you can gradually unlock. And then comes the fun really begins, they experience many crazy things. Even if you dream, you can watch their dreams and comes from the laughter barely out.
The highlight for me is the music stage - when the Miis learn a Level (which always happens when you solve enough of their problems to their satisfaction), you can teach them a song that they can enter solo or as a band the best. Depending on the style of music the songs are indeed always the same, but you can enter text freely. A lot of fun, if then, for example, Finn, Jake, Princess Bubblegum and Marceline in Visual-kei style (called the game "Metal") singing about the Ice King.
I am curious what will happen to my island everything for funny things. Although the category of her more "special interest", but who have games like "The Sims" like (to have), which should look at Tomodachi Life definitely once.