Sure! Here's an example of a simple UFO shooting game implemented as a single HTML file using JavaScript. The game can be played on a smartphone and includes pictograms for UFO and airplanes. You can copy the code below and save it as an HTML file to run it in your browser:
To play the game on a smartphone, open the HTML file in a mobile browser, and you can control the UFO's movement using touch gestures. Tapping the screen fires bullets from the UFO to shoot down the airplanes. Avoid colliding with the airplanes, as they are trying to catch the UFO.