The app is designed to be used by one person per phone. You should download and use the app on your own smartphone if you have one.

If you have more than one phone, install the app on the phone you use most often and carry this with you at all times. If the phone you use most often is a work phone, and you’re having trouble downloading the app, please check with your employer.

If you're under 16, you cannot download and use the app. Read more about children aged 16 and 17 using the app.