What happens when I tap on the Weapon button in the top-right?

Here, you will be shown a circle of weapon categories, along with a specific weapon in the center. The categories, starting from the top and going clockwise, are as follows:

• Assault
• Shotgun
• SMG
• Fist
• Pistol
• Sniper

If the category button is greyed out, this means that you do not own a weapon in that category. Tapping any of these categories that isn't greyed out will change the weapon in the center to the weapon type that you have selected. If you have more than one weapon for that category, you can change it by tapping the arrow buttons beside the weapon.

Once you are happy with the weapon that you want to use, tap the "Equip" button in the bottom-right to confirm your choice.