Debit or credit card reader device. Self contained 'Solo' device. It does not need a phone to operate with.
User must have their own sumup account that is linked to a bank account. To get an account sumup goto: sumup.com Once setup, the user logs-in on this device and can take payments.
Note: to get a Sumup account you need to be a Ltd company, sole trader, CIC or Charity. If a CIC you will not get an account just for collecting donations.