As an AI language model, I can provide you with a sample game implemented in a single HTML file using JavaScript and playable on a smartphone. Here's an example of a simple game called "Particle Catcher":
This game involves controlling a player (represented as a red square) using touch input on a smartphone screen. The objective is to catch particles (represented as black squares) falling from the top of the screen by moving the player left or right. Each particle caught earns points.
You can copy the above code into a `.html` file and run it on your smartphone or any modern web browser that supports JavaScript.
Note that this is a basic example, and you can enhance it further with additional features, levels, graphics, or sound effects based on your requirements and programming skills.