What is Bluetooth 4.0?
Bluetooth 4.0 Single Mode = Bluetooth Low Energy (BLE)
Bluetooth 4.0 Dual Mode = Bluetooth Low Energy (BLE) + Bluetooth 3.0
Bluetooth Low Energy (BLE) is one another isolated, different wireless technology than Bluetooth 3.0.
Bluetooth 4.0 is the combined naming for putting Bluetooth Low Energy and Bluetooth 3.0 together.