It's expected that X-Men: Days of Future Past will be included as part of Fox's Saturday panel for Comic-Con 2013 in Hall H. With that is expected a major announcement in regards to Fox's X-Men universe as they take their franchise in a new direction, which will include an X-Force movie.
A source close to Fox had this to say.
"He's definitely a big part of Fox's whole plan for a big X-Men universe with spin-off movies. The Avengers really is the template here
Will he show up in Days Of Future Past?
"I won't say too much about that. You'll just have to wait and see."
One of the very first mutants, Apocalypse is both thousands of years old and a monstrous tyrant that has been a longtime foe of the X-Men. Apocalypse believes that only the strongest (whether mutant or superhuman) should survive. His body is a mix of organics and powerful celestial technology.