NHS contact tracing app: How does it work and when can you download it? 

With Britain in lockdown, the Government has been racing to find ways to ease restrictions without putting public safety at risk.  

One solution that has been promised is a contact tracing app. The UK Government has announced the infrastructure was being put in place so that contact tracing could be rolled out on a large scale.

"As we look ahead, this is critical to keep the virus under control," Matt Hancock said on April 23.

The Health Secretary said a new NHS contact tracing app was undergoing testing.

From teams of "corona detectives", to Army cadets making thousands of calls a day, here are some of the ways countries are tracing the spread of Covid-19.

But what exactly is contract tracing, can it really help lift the lockdown measures, and when will it be available? 

What is it and how does it work?

A contact tracing app is designed to let people know if they have been in close contact with someone who later tests positive for Covid-19.

It has been billed as a tool that could help pinpoint exactly who needs to be in quarantine and who doesn’t, making it a key to easing up social distancing measures.