It seems that you can play by downloading and use the html file on either browser or joiplay (an app a lot of ppl mentioned here, but idk anything about it). Or, just play on the browser.
I personally prefer, and had only play on the browser as I don't need to download anything. There's a button for that, with "Run game" as its text. Though tbh, I feel like the UI would look better on PC/Desktop than on mobile. But it's still usable