What happened to Britain’s track and trace app?

Excerpt from article:

“Yes of course it’s perfectly true that it would be great to have an app, but no country in the world has a functioning track and trace app,” Boris Johnson claimed last Tuesday in the House of Commons. Keir Starmer calmly pointed out that Germany has precisely such an app. This prompts the question of who is advising the UK Government on technology and how our Prime Minister could be so misinformed.