Update 04/19/2015: Updated for Xcode 6.3 / Swift 1.2 Update 11/17/2015: Updated for Xcode 7.1 / Swift 2. Update 10/19/2016: Updated for Xcode 8.0 / Swift 3. Creating machines that interact with the physical world is an incredibly satisfying thing. Controlling them via Bluetooth with your iOS device is just plain awesome! In the past, the only way to create an Apple-approved Bluetooth device was by