Sure! Here's an example of a simple platformer game implemented as a single HTML file using JavaScript. It can be played on a smartphone and uses pictograms for visuals:
This example creates a platformer game where the player is represented by a blue square. The controls for the game are implemented for touch input on a smartphone, where tapping the left half of the screen moves the player left, tapping the right half moves the player right, and tapping the top half makes the player jump. The player also experiences gravity and can collide with the ground.