Apple Pay launched in the UK last summer, and made relatively swift progress adding banks. However, there was one notable holdout: Barclays, the country's second biggest bank. Today, though, the company has announced it's adding support for Apple Pay. Barclaycard holders will be able to add their debit or credit cards to the app, and then pay using their iPhone, Apple Watch, or iPad at the UK's 400,000 or so compatible locations. You know how it works.