1.1, 1.2
- Speed of 1 Mbps
2.0, 2.1
- Backwards compatible with first generation
- Supports Enhanced Data Rate which pushes top speed to 3 Mbps
3.0 (Bluetooth High Speed)
- Speed of 24 Mbps
4.0, 4.1, 4.2 (Bluetooth Smart)
Improves speed, reduces power and increases security
5.0
- Allows fine tuning speed at the expense of range
- Support for Internet of Things