I have an iPod Touch and received this for Christmas. Upon plugging the iPod into the game, a popup announces that charging is not supported with this device. However, the "Dismiss" button is unreachable, so it basically locks up your iPod until you pull it out of the game, and then we're back to needing to plug it into the game.
Fortunately, my wife has an old 4th generation iPod, so we were able to plug hers in and play the game.
The game plays a playlist or entire contents of the iPod plugged into it. It selects a random song, plays it from the beginning, and each player has a buzzer they can use to stop the playback and answer based on the card that was drawn. Usually, it is a combination of Song, Artist, or Album. The iPod can be popped up out of the game chassis without disconnecting it to check the correctness of the answer. The correct answer scores that player points based on the card that was drawn. High score wins.
One thing I should note is that the owner of the iPod will have a serious advantage in the game, especially if it is the only iPod available, because they will be far more familiar with the songs than anyone else playing. For that reason, we chose discs that everyone agreed on, made a new playlist, and then used that for the game. We had 80 songs and 6 CDs on the playlist, and that was good to have a game that lasted a couple hours.
Overall, the game is fun and works the way it should. However, one card is "broken," meaning you can't score it correctly while playing. That is the "Challenge" card. If you get that card, you get to challenge another player. That player can answer and either gain points or lose points, but since you were the one that buzzed in, the points are only going to be applied to your score. You have to make a note that the next time the player who was challenged buzzes in, you have to carry over the score from the Challenge round.
I would also recommend playing with a computer and an internet connection. After all, once you buzz in, there is no way to continue playing the song that was buzzed. On the "Karaoke" card, there is no way of checking the answer aside from having a lyrics sheet available. You also need to be able to verify if the player has correctly answered a card that wants another album by the same artist.
So if you have a computer nearby with an internet connection, and you have a Classic iPod, this game is fun to play. There are enough limitations that I wouldn't recommend it casually. The designers made an electronic product that works fine, but seems to suffer from a lack of play testing.