Sure! Here's an example of a simple Tetris game implemented as a single HTML file using JavaScript:
To play the game, you can open the HTML file in a web browser on your smartphone. The game is controlled using the left, right, down, and up arrow keys. The objective of the game is to fill and clear rows by fitting tetromino shapes together. If the stack of tetrominoes reaches the top of the grid, the game is over. The interval speed can be adjusted to change the game speed.