Use of the app is voluntary and employers cannot force their employees use it.
Employers may encourage employees to download the app and register to use it, by sharing the NHS COVID-19 app information website.
If you have more than one smartphone, you can choose to download and register the app on a preferred phone. Use the app on the phone that is with you most of the time. This might not always be a work phone. This will make sure the app protects you as much as possible.