Just for curiosity, I was playing around and found this article, explaining how to add websites to any phone or tablet...
https://www.howtogeek.com/196087/how-to ... or-tablet/
Then, using the URL flagged up in Xfool's link to the Guardian website, I added https://www.nathanmediaservices.co.uk/teletext-viewer/ to the home screen, and voila! Ceefax on my Android phone.
Fun to mess about with
