What is the difference between Dragonflow and other open source SDN controllers?

Dragonflow doesn't aim to become a full featured SDN controller with application running on top of it.
The purpose of Dragonflow is to enables DVR and virtual networking connectivity in a simple and easy way that integrate almost seamlessly on top of Openstack Neutron and doesn't require any additional components or installations.

 (The Ryu SDN framework is used for Openflow handling but this is transparent to the user)