Used with MMI 3G Plus in a 2014 A4 (yes A2DP is an option when the Audi Bluetooth is present by default), it allows me to have the iPhone, iPad, iPod touch, the Xperia Z1 or Xperia Tablet Z Bluetooth and share all of their audio content in the car without having to leave them in the glove box (where neither the iPhone 5 or the iPhone 5S were recognized via the specific cable purchased from Audi).
Now I can enjoy all my audio content without restriction. A huge YES to this little device.