Go to Settings > Security and allow installation from "Unknown Sources" to install downloaded APK files.
If version 412.0.0.0.5 still runs slowly or crashes on your device, consider switching to . This is an official, stripped-down version of Facebook maintained directly by Meta. It uses less than 3MB of space, works on 2G networks, and is designed specifically for low-end hardware without the security risks of using outdated software. To help find the right version for your device, tell me: What Android version is your phone running? facebook 4120005 apk older versions for and work
Help you find a (like Facebook Lite) if an older version doesn't work. Go to Settings > Security and allow installation