Sure! Here's a simple platform game implemented in a single HTML file using JavaScript:
This game is a simple platformer where you control a blue square (representing the player) using the spacebar to jump. The goal is to avoid falling off the platform (green rectangle) by timing your jumps correctly.
To play the game, open the HTML file in a web browser on your smartphone. Tap the screen to focus on the game, and then use the spacebar on your smartphone's keyboard (if available) to make the player jump.
Note: This game is a basic example and can be further enhanced with additional features like multiple levels, score tracking, and enemies. Feel free to modify and expand upon it as per your requirements.