Bluetooth is simultaneously useful and annoying. It's great when you can get it to work, but the annoyances with Bluetooth audio are why many passed on the jack-less iPhone 7, Moto Z, and HTC U Ultra. Among the many other features of the Samsung Galaxy S8 is Bluetooth 5 support; it's the first phone to include the new standard.
If you're unfamiliar, Bluetooth 5 (officially, there's no version number, like 4.0 had) is a fairly major upgrade from Bluetooth 4.0. It has double the bandwidth speed (2 Mb/s), 4x the range, and support for long-range low energy Bluetooth connections.
That extra bandwidth is required for the Galaxy S8's "Dual audio" feature. This allows the phone to stream audio to two Bluetooth headsets or speakers at the same time. You can also adjust the volume for each device independently. It's like sharing an earbud with your friend, except with fewer wires and less bacteria.
- The Verge