Sure! Here's a simple game in which you can control and move a square using the arrow keys on your smartphone. Please note that this code snippet is just a basic example and may require further development to meet your specific requirements.
To play the game, you can open this HTML file in any modern web browser (preferably on your smartphone) and use the arrow keys to move the square around the screen. The square will move 10 pixels at a time in the specified direction. Feel free to modify the `stepSize` variable to adjust the movement speed according to your preferences.