Sure! Here's a basic implementation of a Pong game in a single HTML file using JavaScript. Please note that this is a simplified version and may not include all the features of a complete game.
This implementation provides a basic pong game where you can control the paddle's movement on a smartphone by touching and dragging. The ball bounces off the walls and the paddle. Please note that you can further enhance this game by adding scoring, AI opponent, and more advanced features.