Apple has received a patent that could enable users to unlock their devices using their unique heart rhythms, leveraging the ECG capabilities of the Apple Watch. This innovative feature allows users to authenticate themselves simply by wearing the Apple Watch, streamlining the process compared to traditional methods like passwords or fingerprints. The technology involves using sensors to detect electrical signals from the heart, completing a circuit when the digital crown is touched. Future iPhones may also incorporate this capability, potentially allowing them to unlock just by being held. Additionally, the patent hints at using heart data to assess a user's mood and adjust music playback accordingly. While the patent reflects Apple's ambitions, it remains uncertain if these features will come to fruition in actual products.