I have an anecdote from a mobile device manufacturer: a new sensor module was able to provide all sorts of biometric data to a smartphone and just snapped onto

I have an anecdote from a mobile device manufacturer: a new sensor module was able to provide all sorts of biometric data to a smartphone and just snapped onto the phone, no other configuration. The device was shown to a team of top engineers and they were given a couple weeks to develop an equivalent system. The sensing was easy and worked fine, but at the end of the project they could never replicate the seamless pairing of the device to the phone. Left with all sorts of theories about hacked network stacks...they admitted defeat. Only to then learn: the device was transmitting data with inaudible soundwaves picked up by the phone's microphone. What you're hinting at can cut both ways: you can fake the magical, while often the magical is far simpler than you thought.