What is the point of the Covid-19 app? Ministers seem to be as in the dark about the answer to this question as the rest of us, with the government tying itself in knots over whether it means anything at all to get ‘pinged’ and told to self-isolate.

Downing Street has contradicted Business Minister Paul Scully, who said this morning that there was no need to self-isolate if it was just the app that alerted you.