There's no word on who will be playing him, but thanks to the latest Instagram post from director Bryan Singer, we now know that Caliban will make an appearance in X-MEN: APOCALYPSE. In the comics, Caliban can sense the presence of other mutants, and was used by Callisto to find mutants to create the underground community known as the Morlocks.
As to how the character might be used in X-MEN: APOCALYPSE, Caliban has an important connection to the titular villain in the Marvel comics. Caliban served as his Hellhound before being "promoted" to Death, one of the Four Horsemen of Apocalypse. He was also recruited into the X-Force by Cable, and was an X-Factor member, but it's more likely he will be the Death Horseman in the upcoming film instead of part of the X-Men team. Do you think the Morlocks will be in Singer's new movie, and who do you want to portray Caliban?
X-MEN: APOCALYPSE will be in theaters on May 27, 2016.