Here's an example of a simple game called "Cannonball" that you can play on a smartphone using pictograms and implemented as a single HTML file with JavaScript enclosed in script tags:
Score: 0
This game involves controlling a cannon at the bottom using the left and right arrow keys and shooting cannonballs by pressing the spacebar. The objective is to hit the targets (represented by red rectangles) to earn points. The score is displayed at the top. The game continues until all targets are hit.