Leo Kelion, BBC News:

The UK’s coronavirus contact-tracing app is set to use a different model to the one proposed by Apple and Google, despite concerns raised about privacy and performance.

And:

The NHS says it has a way to make the software work “sufficiently well” on iPhones without users having to keep it active and on-screen.

And:

It has opted for a “centralised model” to achieve this – meaning that the matching process, which works out which phones to send alerts to – happens on a computer server.

This contrasts with Apple and Google’s “decentralised” approach – where the matches take place on users’ handsets.

With this basic premise in mind, go read Ben Lovejoy’s piece, titled It’s no exaggeration to say UK rejection of Apple API will cost lives. Smart take.