There are many nice things about frelan software that I can mention :1) The user interface is very intuitive2) It is easy to use3) Easy installation4) Very good support5) Free (although I think there is also an expensive version for some features).
I don't really have anything bad to say but I would love it if they released more documentation for new users as well as those advanced ones who know how everything works inside out. We used this tool for our mobile applications where we needed to connect multiple nodes in order to send messages between them.