good article. Can't wait for the next one.
Now I know that even though two bluetooth devices aren't connected they still can exchange information. This would be good for doing lot's of things other than authentication like... would you have an idea of what could be done with this extra info?
Unless you want to deal with some kind of attachment to the phone, the short answer is to wait until phones start supporting Bluetooth 4.0 – first phones with new Bluetooth IC are expected at the end of this year.
Good thing BLE is an integral part of Bluetooth specification and its proliferation into cell phones is just a matter of time.
First WiFi rolled out WiFi direct a facility already provided by BlueTooth devices. Now BlueTooth is Moving to IEEE802.15.4 space.
I think these three has to converge in single SoC at one one time you are going to use one (Atleast in Mobile Devices not in low cost low power sensors)