We still have two more years before we see X-Men: Apocalypse of the big screen, but director Bryan Singer is already teasing the production of the film. He posted an image of the script treatment that he's written for the film.
From what I can gather, this is a description of a prologue battle sequence. It's set on the Nile, and it involves the Four Horsemen, who were teased in the end credits scene of X-Men: Days of Future Past along with Apocalypse.
The movie is being written by Singer, Simon Kinberg, Michael Dougherty, and Dan Harris, and it's set to be released on May 27th, 2016.