Get a sim card from 3 Mobile, download Wuntu, register and enjoy the World of Discounts: cheap meal deals of £2, £3 & £5 burger at Cafe Rouge, burrito as Las Iguanas, pizza or pasta at Bella Italia and even a free pizza in Domino's. Add to those free occasional coffee from Costa and even cinema tickets, and you'll enjoy London in a new level
Good ideas for a cheap food deal in London, Soho: meals for 5 pounds: Shrimp masala roll at The Kati Roll Company. Probably the best bratwurst in London from Herman ze German. A paradise for cheese lovers at Melt Room who are mainly famous for their Mac and Cheese. You know you can get a good eat when browsing around Soho.