More than one million people have downloaded Scotland’s new contact tracing app since its launch last week.
Protect Scotland became available to download free on to a smart phone from Apple’s App Store or Google Play on 10 September.
The app lets people know if they have been in close contact with someone who later tests positive for Covid-19.
First Minister Nicola Sturgeon called on people to “keep spreading the word” about the app.
The Scottish government has said the software will support the Test and Protect system and is “another tool” in the fight against the virus.
Up until now, contact tracing has been done manually using a method followed for years to help control the spread of infectious diseases.
Last week some iPhone users have reported not being able to download the app because they are not running iOS 13.
The iPhone 6 and older models launched before 2015 cannot run Apple’s latest operating system.
Android phone users will also need to be running at least the Android 6.0 operating system, which was launched in 2015, the Protect.scot website says.
Research by Ofcom from 2017 suggested that about 3.2m adults in Scotland owned a smartphone.
How does the app work?
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.