It doesn't have an official one, sorry.

However, we've got something better a 'Progressive Web App' - or, for short a PWA.

This was favored over building an app by the devs and many users too.

If you've got a browser that can create PWAs when you're on SN you'll have a big, yellow prompt at the bottom asking whether you want to create one.

There's a chance that you might not be getting this message as your browser might not be able to make PWAs. In this case, try another browser and see if that works. See the link above to see which ones do.

You fan still use your normal browser though, you won't see any difference from the PWA really.

Good luck!

The PWA works well for me on mobile.

(Progressive Web App, in case you`re not familiar with the term.)