At UIKonf I gave a talk about Bluetooth LE on iOS (and Mac). The videos for the conference are now available online. Checkout my presentation or any of the other great talks.
Liquid error: undefined method `’ for nil:NilClass
An earlier post I published lists the source code for the demos in the talk.
I also maintain a list of gadgets using Buetooth Smart in case you are looking for some hardware to play with.