First, I just came back from Germany where I've seen that thing in a shop. Didn't have much time to investigate due to the kids, but guessed that it's just NFC chips with data on the headphores.
Second, I've been thinking about building a simple MP3-player for my kids for quite a while now, and (minus the obfuscation there) that's not far from what I've been thinking about doing.
First, I just came back from Germany where I've seen that thing in a shop. Didn't have much time to investigate due to the kids, but guessed that it's just NFC chips with data on the headphores.
Second, I've been thinking about building a simple MP3-player for my kids for quite a while now, and (minus the obfuscation there) that's not far from what I've been thinking about doing.