It is usable on Android. Websites can embed Ruffle in their backend, then everyone can just visit the website and play the flash game / watch the flash animation without installing anything at all. If you play many browser games, chances are good you’ve already used Ruffle. And that goes for mobile browsers as well; I can even play flash games on Safari on my iPhone if the websites embed it.
I’m not sure about if / how you can install the extension (which you can use to access all flash content, even if the websites themselves didn’t embed it) on mobile browsers, but I think that there is a Ruffle app for Android, and a demo page used to execute any swf (flash) files.
However, most flash games are made for computer and some may even require mouse hover events or something which just doesn’t exist on any mobile phones. So while Ruffle works there, the flash games of course also need to be playable with a touch screen.
Historical_General