Apple is selling WorldPay Zinc mobile chip-and-pin keypads at 37 retail stores in the U.K.

WorldPay, one of the U.K.'s largest merchant acquirers, expects the mobile point-of-sale market there to grow significantly over the next 12 months, driven by increased usage among its 4 million small businesses and sole proprietors.

In addition, WorldPay Zinc is launching an optimized app for iPad; the service had been available to iPad users since the keypads launched in June, through the existing app for iPhone and iPod touch, but the company said the optimized app provides an improved experience for users on the larger iPad display.

WorldPay doesn't require long-term contract commitments or monthly subscription fees and charges a 2.75 percent fee per card payment.

Geraldine Wilson, managing director of WorldPay Zinc, said the solution has been widely embraced.

"We've seen WorldPay Zinc being used at music festivals, at foodie and art fairs, at home jewelry sales and by mobile locksmiths, plumbers, creative designers, nail technicians, dog walkers and many other people who would previously have been restricted to taking cash and check payments," she said in a news release. "People really like the compact, 'pocketable' keypad design and the freedom it gives them to take cards. This represents a really exciting moment in the growth of mobile card payment acceptance."

The keypad is available for £59.99 at Apple retail stores in the U.K. The WorldPay Zinc App is available free from the App Store.

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