This page compares Bluetooth 5 vs Bluetooth 4.2. The basic features of Bluetooth 5 which has made it popular for IoT(Internet of Things) and Bluetooth Beacon markets. Bluetooth 5 is the latest Bluetooth specifications the successor to Bluetooth 4.2 version.
The Bluetooth 5 is backward compatible with previous Bluetooth versions such as v1.2, v2, v2.1, v3, v4, v4.1 and v4.2. The specifications address the requirement of IoT devices which is lower power, longer range and higher speed. Due to these features, you could find Bluetooth 5 being incorporated in smart phone devices coming up in the early 2017.