Have not tried to use this offer yet but got an email through and upon checking the site the offer is valid for each person paying via the paypal app so:
£2.40 for soft drink (or anything you want) per person.
Pay with paypal app
Free Burger or Buritto!
Not on every high street but do have a few restaurants and taste is pretty good.
This can be for anything from the cost of £1 (tea 1.95, olives 2.95, maybe tip £1?? etc)
Knowing HUKD this will go cold as they don't have enough stores or something but seems a great deal as far as I am concerned.
Available until 11th August - Extended to the 25th August