Fewer buildings on phones. For the full town, play on a computer.
Graphics sets the detail. Ultra needs WebGPU and switches it on by itself; on 157 mountains so far (falls back to High elsewhere). High runs on either engine; Medium and below use WebGL.
Ultra needs WebGPU — set the engine to Auto.
Auto picks the best engine for your browser. Choose WebGL only if you see glitches. (On WebGPU, High also draws a denser forest.)
Minimum requirements: a current browser with WebGL 2 working on your device, an internet connection to load the mountain, and a keyboard, standard gamepad or touch controls. Performance varies by device and mountain.
Slower laptop or phone? Try Low, then Phone or Phone lite (the lightest setting, also for laptops). Changing graphics reloads the mountain. Low cannot fix missing WebGL 2.