Did you know your phone can wirelessly beam electricity through the air? Here are the energy harvesting NFC padlocks that prove it. Your credit card doesn’t need a battery for tap-to-pay, and neither do they, because your phone provides the juice the same way. You slowly charge their embedded capacitors until they can turn an electric motor to pop the shackle. Not that I’d recommend them: these cheap locks don’t feel very secure, their apps ask for lots of permissions, and they’re really finicky