The spectator scans a QR code using their own phone. A music player loads on their phone, with a single song queued. Then, they freely choose any card.
When the music starts playing on the spectator's phone, the entire lyrics are about a single card. Incredibly, the card mentioned in the song corresponds exactly to the chosen card.
No forcing. Any card can be named — even the joker.
You don't touch the spectator's phone.
No NFC.
No memory work.
Works on iOS and Android.