Verified legacy versions are available on APKMirror . 3. The Browser Workaround (Most Reliable)
For a device on Android 4.1.2, you cannot use the standard Google Play Store version. Instead, you must source a compatible "legacy" APK from third-party archives like Facebook (Main App): The last major version to support Android 4.1+ (API 16) was v281.0.0.36.124 , released in August 2020. Facebook Lite: facebook apk android 412 work