There is no official standalone APK for "FNaF 4 Halloween Edition" on Google Play. The Halloween content is unlocked in the paid FNaF 4 app (by Scott Cawthon / Clickteam) via a free update.

Stay safe, stay vigilant, and keep the doors shut tight.

: Community members have created unofficial mobile versions of the Halloween update, such as those hosted on mod.io or itch.io .

Turn around periodically to flash your light at the bed to scare away Mini-Freddys (Freddles). Check the closet to keep Nightmare Mangle from fully manifesting and attacking. Step-by-Step Guide to Download and Install the APK