A new generation of Bluetooth audio improves efficiency and sound while adding a broadcast feature, letting one device send audio that many headphones can tune into at once, rather than pairing one to one. Support has been spreading across phones, earbuds and public venues.
This enables silent gyms where screens broadcast sound to any listener, airport announcements sent straight to earbuds, and shared listening between friends. The lower power use also helps battery life and hearing-aid style devices. As with any standard, the benefits appear only when both the source and the earbuds support it, so the rollout has been steady rather than instant.