My hearing was seriously degraded from flying my hot-air balloon with the loud burner next to my head. I now have to wear small hearing aids to fill in a certain frequency range.
I can buy 2 external devices at $500 each which will allow limited "fine tuning and adjustments" of my devices via bluetooth without having to schedule a trip to the audiologist. Neither is the full package, I would need to purchase both. I am quite interested in an app for the iPhone which would allow me to adjust the settings, volume, balance, etc., and pass phone, music, and other audio directly into the headset via bluetooth.