Filecoin Dead Drop is a tiny treasure-hunt app for the FilecoinTLDR Builder Challenge. A builder writes a clue, seals it through the Filecoin/Synapse storage flow, and gets a PieceCID. That PieceCID is the dead-drop key another player pastes back into the app to retrieve and reveal the clue. The CID is the product mechanic rather than a hidden backend detail.
