I bought this dog for my daughter for christmas. she tried it in her 2nd generation nano and it froze up immediately and then went dead. we had to return her nano and get a new one which luckily we had just bought and could still return it. I know when new ipods come out they often have compatibility issues with some products and this was definitely one of them. I wanted to make sure people know there is a chance they may ruin their ipod and use caution if purchasing this dog for use with 2nd generation nanos...