Sure! Here's an example of a simple game using JavaScript and three.js, where you can control a gun using touch events on a smartphone:
In this game, you can control the gun by dragging your finger on the screen. When you press the "Shoot" button, a yellow particle is emitted from the gun for two seconds before disappearing.
Please note that this is just a basic example and can be further customized and enhanced according to your specific requirements.