When did Bluetooth headphones become popular?

Towards the mid-2000s, Bluetooth stereophonic headphones also made their debut. But it would take until the early 2010s for them to become widely popular, and truly viable alternatives to more traditional headphones. Bluetooth headphones are now almost as ubiquitous as regular headphones today.

Who first came up with wireless headphones?

Courtney Graham, a United Airline pilot himself, along with his friend and fellow pilot, Keith Larkin, decided to create a headset that was both durable and light. The two pilots ended up attaching two transducers, as used in hearing aids, to a headband. The design was submitted to United Airlines who approved it.