England's Covid contact-tracing app will reach 70% of those at risk

Tech will tell users who spend 15 minutes within 2 metres of another app user who has tested positive to self-isolate

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The re-designed NHS contact-tracing app, which begins trials in the Isle of Wight, will correctly identify seven out of 10 people who spend more than 15 minutes within 2 metres of another app user who has tested positive for coronavirus and warn them to self-isolate.

The new app has been designed in collaboration with Google, Apple and other tech companies so that it works with 99% of phones. It no longer has the major failing of the original which did not work with iPhones.