This is the only Five Nights at Freddy's game that includes phone guy but faintly and garbled in the background.
The game was originally supposed to come out Halloween day in 2015.
This is the first game that you aren't a night guard, are in a house, can actually move your character, and DON'T have security cameras.
The animatronics in this game are confirmed to be "Nightmare" animatronics
While creator Scott Cawthon did, in fact, originally plan this game to be released around Halloween of 2015, it was indeed released early in July. However, Cawthon has mentioned that Downloadable Content will be available instead around Halloween. [August 2015]