How do I link more users to the account?

Users are created in the Web

Go to the Administration tab
Select submenu Users and Create new User

Give the user permissions
For a new user to be able to connect you need to give access to mobile client. You do this in the same step as you add the user.
Additionally, you decide what rights the user should have by quickly ticking the boxes.

Now, the new user connect to the account by entering username and password in the app.