Sure! Here's a simple tower defense game implemented as a single HTML file with JavaScript. The game includes upgrades, multiple tower options, and the ability to select different maps. The game is designed to be played on a smartphone and uses pictograms for the towers and enemies.
Please note that this code provides a basic structure for a tower defense game and includes placeholders for game logic, map selection, tower selection, and other features mentioned in the requirements. You'll need to add the actual game mechanics, graphics, and implement the missing functionalities based on your specific requirements.