Sure, here's an example of a simple 3D racer game implemented as a single HTML file using JavaScript. The game can be played on a smartphone and uses pictograms to represent the game elements.
In this game, you control a player represented by a red block using the left and right arrow keys on your smartphone. The objective is to avoid the blue blocks falling from the top of the screen. If the player collides with any of the blocks, the game is over, and an alert message will be shown.
Note: This is a simplified example for demonstration purposes and lacks advanced features, graphics, and optimization. Feel free to enhance and customize the game further as per your requirements.