Can I open two EASessions for communicating with external accessory? One EASession for control command, the other EASession for streaming data.
I recommend reading the manual for EAAccessory, as it clearly states:
For a given accessory object, only one session at a time is allowed for a specific protocol.
So, yes: As long as the protocols are different, you can have multiple sessions. If they aren't, is there anything preventing you from using a second EAAccessory object..?