Scotland's new contact tracing app to help combat the spread of coronavirus has gone live.

The Scottish government has said the software will support the Test and Protect system and is "another tool in the fight against Covid-19".

The Protect Scotland app lets people know if they have been in close contact with someone who later tests positive.

It can be downloaded for free onto a smart phone from Apple's App Store or Google Play.

First Minister Nicola Sturgeon has urged as many people as possible to get involved in the new tracing scheme.

She tweeted on Thursday morning: "There's a new way to help fight Covid in Scotland. 'Protect Scotland' - our confidential contact tracing app - will anonymously notify app users you've been in close contact with, should you test positive.

"Please download, and let's all protect Scotland."

Up until now, contact tracing has been done manually using a method followed for years to help control the spread of infectious diseases.

Anonymous alert

The new app uses Bluetooth technology to alert users if they have been in prolonged close contact with someone who subsequently tests positive for Covid-19.

When an individual initially tests positive for the virus, they are contacted by phone in the usual way.

The contact tracer will ask them if they are an app user and if they are willing to use the app's upload function to anonymously alert close contacts.

If they agree, they will be sent a unique code to their mobile which unlocks this function on the app.

By sharing their positive test result in this way, the information will form part of an anonymous database.

The app on other users' phones regularly checks this database to see if they have been in contact with an infected person.

A warning is automatically issued when a match is found and users are then urged to get tested or self-isolate for 14 days.

Another contact tracing app being developed by the NHS in England ran into technical problems and is currently being tested following a revamp.

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