It is built for phones first: portrait or landscape, one-thumb controls, and it runs fine on mid-range hardware. Desktop keyboard controls work too.
This build has its own tuning - a 5×10 brick wall and a paddle tuned to 16% of the screen. Your progress and best score are saved locally on your device.
Your best score is stored in your browser's local storage, so it survives refreshes. Clearing site data resets it.