Nick_Pyner:
If you are referring to anything other than plain vanilla BT2 SPP protocol, then you have just left HC-05, and bought a passage into another world, where it is time to come to terms with the programming adventure that entails.
I want to put another program aside the UART bluetooth line with the GPIO's and maybe some more advanced communications just using the NRF5 due to the cost and low space constrains.
Nick_Pyner:
No. This is bluetooth. It is a system more for convenience than high security, but the security it has should be quite satisfactory for normal people. If you are getting paranoid, moving to BLE might help somewhat, as I understand they all use a six-digit password for pairing.
Well then, How do you implement that password in arduino? Also probably the right term for what I want to achieve is Bonding, I need to can a single communication line and bond a smartphone to the NRF5 chip.