Sure! Here's a playable sample game of Tetris implemented as a single HTML file using JavaScript:
You can copy the above code into an HTML file and run it to play the Tetris game. The game grid and Tetris pieces are displayed on a canvas element, and you can control the pieces using the arrow keys on your smartphone to move them left, right, or rotate. The objective is to clear as many lines as possible by filling them completely with Tetris pieces.