Its ok I have figured it out. I was confused about the capability of this feature.
I can connect my phone to the player and play the tracks and/or I can connect to Rekordbox wirelessly and transfer music to my phone in order to dj with them but I can't use the phone as a bridge to Rekordbox which I thought I could.
Shame
Perhaps Pioneer should look into whether this is a possibility. Or alternatively I could invest in a wireless bridge...