It seems like the bluetooth function on the Ak120 is receiving rather than transmit as I understand it can receive bluetooth streaming from bluetooth 3.0 devices and above. You can use an iphone or android and bluetooth stream music to the Ak120 but I am not sure nor tried the bluetooth to transmit or to stream music using the Ak120 as a source though. Will check out and revert bk here.
The AK120 can connect to both my iPhone and Android devices but not my car stereo system.
That is what I am thinking now. But if the AK120 has latest Bluetooth version, it should compatible backward just like USB 3.0 and 2.0. I will check it more careful on tomorrow.