"Call of Duty: Black Ops 4" does not exist on Android. The search for an APK/OBB version is a trap set by scammers to exploit fans of the franchise. The only safe way to experience the franchise on mobile is through the official Call of Duty: Mobile application.
: You can technically play the full PC or console version of Black Ops 4 on Android using cloud streaming services or PS4 Remote Play , provided you already own the game on those platforms. Risks of "Black Ops 4 APK" Downloads Call Of Duty Black Ops 4 Apk - Obb For Android
Stay safe, and enjoy legitimate mobile gaming. "Call of Duty: Black Ops 4" does not exist on Android
While a native APK does not exist, players use these official streaming methods to play the console/PC version of BO4 on their phones: How To Download Call of Duty Black Ops 4 on Android : You can technically play the full PC
Without both files correctly installed, the game will crash or fail to load.
: Since the game isn't official, it will lack security updates, bug fixes, and active multiplayer servers. Authentic Black Ops on Mobile