Question on the conversation between the Android and the BLE

We bought CA-SDK. [What I have found] After looking at the code, BluetoothDataReader.java Method synRead() simply looks for the first byte to be a '$' or not and if not it discards the rest assuming that the datastream in out of sync. Once the data stream is found to be in sync the method readData() reads packets of data 23 bytes long and dispositions them in buffers.

2. Questions:
* What calls synRead (), and readData() Where does the process start from ?
* Since the Blueradion advertises that it supports standard 'AT' commands (which are well documented) where are these being written to the device ? Where is the OutputStream OSStream ... Where is the BlueToothDataWriter.java ???
* Are we relying on the standard 'AT' command set or does the wearable device have custom firmwear that uses a different protocol ?

Thanks,