Press the left side of the screen to move your tank around. Hold the right side of the screen to shoot. Buy new weapons between levels, and then tap the icon to switch to them.
Move your tank with the arrow keys or WASD. Aim your tank and fire with your mouse. Defeat enemy tanks, collect coins, and destroy the enemy base in order to clear each level. Spend your money wisely to upgrade your tank with better armor, weapons, visibility and more.
If you have trouble moving and firing at the same time, try using the arrow keys to move instead of WASD or vice-versa.