GoKawiilEngineer builds NFC business card with phone-powered LED, no battery
A developer designed a credit-card-sized PCB business card featuring an NFC chip that opens his website when tapped and a red LED that lights up on a printed Charizard's tail, powered entirely by the phone's own NFC radio field rather than any onboard battery. He had to write a custom Core NFC app for iPhone because standard NFC apps couldn't write to the blank NTAG I2C Plus chip he used, so his app sends the chip's native write commands directly.