Square is today launching a new set of APIs under the “Build with Square” banner that will allow sellers to use Square payment services and hardware (including Apple Pay), while maintaining a customized point of sale experience that might be crucial to their business.

The new Register API allows customized iOS point of sale apps that integrate with Square payment services. In other words, if Square’s stock register apps don’t cut it for a specific business, they can now use the Register API to build their own app that taps into the Square Register app and hardware to process payments:

With our Register API, any iOS point of sale can be customized to process payments with Square. We know that some sellers — especially in retail, like bike shops or wineries — have highly individualized point-of-sale needs. By integrating with Square, sellers with a third-party point of sale will be able to use our beautiful and affordable hardware, accept EMV payments and Apple Pay, and receive the same fair and transparent pricing and financial services available to all our sellers.

And in addition to the new Register API, Build with Square includes an E-commerce API that allows a similar experience on the web:

With our E-commerce API, sellers can use Square to process online payments on their own self-hosted, fully developed website. By seamlessly integrating their website with Square, omnichannel sellers can now have a powerful solution to grow both their online and offline businesses together, tracking all sales — no matter where or how they’re made — in one dashboard.

You can sign-up for a developer account for access to the new Build with Square APIs, which also include APIs for item and inventory management, aales reporting and analytics, and employee management.

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