At the end of Revenge of the Sith, Yoda tells Obi-Wan that he's able to communicate with Qui-Gon, who of course teaches Obi-Wan and Yoda the vanishing Jedi death power (which is a bit odd, since Qui-Gon's body didn't vanish at all).

So presumably he had some kind of communication with Obi-Wan on Tatooine, much like Obi-Wan and later Yoda and Anakin would later appear to Luke.


Is it possible we'll see Qui-Gon appear? Granted, Liam looks a bit older, but he could perhaps just do the voice like in Clone Wars. Also, although the Luke on Crait wasn't a ghost, it was still a sort of force projection that hints that perhaps they can change form (As Luke appeared with shorter hair, a different outfit and slightly younger look); The Force Awakens concept art hinted at doing this with Vader, who would appear as a ghost and shift between his Anakin and Vader forms.