Barclays will be the first British bank to allow people to send payments using just the recipient’s Twitter username. The free service will launch on March 10 for users of the social network and the bank’s Pingit mobile payment app. “Adding the ability to pay people or a small business using just a Twitter handle brings together a social and digital experience to create a new step forward for mobile payments in the UK,” said Darren Foulds, director of Barclays Mobile Banking and Pingit.