Are DJ performances possible using rekordbox (iOS/Android) and this unit, without using rekordbox (Mac/Windows)?

Yes, even without using rekordbox (Mac/Windows), DJ performances are possible with rekordbox (iOS/Android) installed on a mobile device and this unit.

If you already have music files on your mobile device, they can be loaded onto this unit. Playlists can be created using rekordbox (iOS/Android).