They are not really comparable in any way. Luminair is actually a self contained light board without any hardware I/O. If you are looking for something to do that then by all means get Luminair. On the other handiRFR is a remote focus unit app that communicated with the Ion. If you want RFU functionality than get that. Given that you have an Ion, I am guessing you are looking for RFU-ness so get the iRFR and a suitable wireless access point. It is also cheaper as I am sure you know.