The film is more for the fans of Fnaf, I've been a fan since I was 12 so it was easier for me to understand and enjoy where as new comers might be a bit more confused. Still enjoyable for both sides though. My only major disappointment was the springlock failure at the end wasn't as climactic and the jump scares were kinda spoiled in the trailers so I knew when each jump scare was going to happen. Other than that I really enjoyed the personality of the characters in the movie and it has so many wonderful easter eggs. It also knew to not take itself too seriously, and had some good laughs too.
Edit: I really enjoyed the movie a lot more the second time. The springlock failure was better than I thought, I think I was just too shocked it was happening!