A technique that users of AirPods employ to communicate with each other when in close proximity. AirPods swapping is accomplished by exchanging each other's left or right earbuds, and each person hears whatever audible sounds the other person's phone is making, typically via a text-to-speech function. This technique started in a classroom as a way to alert friends without them having to pull out their phone to view a text message. Of course, the sender's actions are not concealed because he or she has to run the app that is generating the audible message. See
AirPods.