Multiple users are able to share a device and mobile phone number to access their NHS account, however all users will need to have their own unique email address. Email addresses are a unique identifier for each account and cannot be shared.
We would ask that you consider the privacy implications around sharing a device and be mindful of logging out of your relevant account after each usage to prevent any unwanted access from others sharing the same device.
To log out of the NHS App, select 'More' then 'Log out'. Alternatively, remove the app from the queued apps on your device.