: If you're on Android, go to Settings > Security, and enable "Unknown Sources." On iOS, you might need to jailbreak your device or use a third-party app store.
: Mods can sometimes cause instability or conflicts with the game's updates. If you're playing on a platform that supports it, consider making a secondary account for modded gameplay to keep your primary account safe.
Frontline Commando: D-Day Mod APK is a modified version of the popular third-person shooter developed by Glu Mobile