Kevin Townsend

“For hardware, you’ll need an Android device running Android version 4.3 or later. While Android began supporting BLE version 4.3, we recommend a device running at least version 4.4, which includes an updated and more stable version of the BLE protocol stack. You’ll also need to make sure the hardware supports Bluetooth Low Energy.”
― Kevin Townsend, Getting Started with Bluetooth Low Energy: Tools and Techniques for Low-Power Networking

“Apple Notification Center Service with an External Display The Apple Notification Center Service (ANCS) function in iOS is the source of notifications displayed as a banner message along the top of the active screen (or in place of the entire active screen) for timely alerts (e.g., when you receive a text message, miss a call, or for a variety of other applications). For example, when you receive an incoming call, the ANCS temporarily replaces the active screen with the screen shown in Figure 9-5. Figure 9-5. A notification of a phone call on an iPhone When iOS 7 was introduced, Apple included a BLE interface to the ANCS to route similar alerts to BLE connected accessories — for example, a BLE-enabled watch.”
― Kevin Townsend, Getting Started with Bluetooth Low Energy: Tools and Techniques for Low-Power Networking