Sure! Here's a simple platform game that meets your requirements. It uses pictograms for the characters and implements increasing difficulty upon each death. Simply copy and paste this code into a single HTML file, and you should be able to play it on your smartphone.
Platform Game
To play the game on your smartphone, open the HTML file in a web browser, and you'll be able to control the player character by tapping on the screen to make it jump. Use the left and right arrow keys on the keyboard to move sideways. The goal is to avoid colliding with the enemies and stay alive as long as possible. Every time you die, the game gets harder with more enemies spawning. Your score increases for every successful jump over an enemy. Enjoy the game!