Army Defender is an action shooter in which players must defend their base against enemy attacks by controlling a machine gun tower designed to eradicate enemy waves. As the player levels up, the enemy becomes more and more numerous and well-equipped. Attackers include soldiers, tanks, paratroopers, helicopters, jet fighters, bombers and elite commandos. Depending on the enemy type (red or green), players must switch between ammunition colors. The machine gun tower will fire where the player taps the touch screen. Power-ups are made available on a regular basis when a super bomber delivers them onto the base. When a power-up is retrieved, players will be able to upgrade their tower for a limited amount of time. Upgrades include flamethrowers, rocket launchers or concussion grenades that will help contain enemy progression.