Sure, here's an example of a simple game implemented as a single HTML file using JavaScript and enclosed in script tags:
When you open this HTML file on a smartphone, you will see a single box pictogram (`📦`) displayed on the screen. Every second, a new box will appear in a random position. When you tap on the box, your score will increase by one and the box will disappear. The current score will be displayed on the screen. The game will continue indefinitely, allowing you to tap on as many boxes as you can.
Please note that this is a simplified example for demonstration purposes and can be further expanded and enhanced based on your requirements.