Sure, I can help you create a simple game in a single HTML file using JavaScript. Here's an example of a basic game where the player controls a character using smartphone touch gestures. The game is enclosed in script tags and uses pictograms for visuals:
In this game, the player can control a square character by swiping on the smartphone screen. The character will move towards the direction of the swipe gesture. The game loop continuously updates the canvas to ensure smooth animation.
Please note that this is just a basic example, and you can further expand and customize it according to your requirements.