Developers in South Korea can now use the payment system of their choice rather than being locked into Apple’s method.

South Korea passed a law requiring Apple to open up the App Store to allow developers to use a payment method of their choosing. Despite Apple’s objection, the law has gone into effect, and Apple has complied. Apple has informed developers of the change in a developer update:

The Telecommunications Business Act in South Korea was recently amended to mandate that apps distributed by app market operators in South Korea be allowed to offer an alternative payment processing option within their apps. To comply with this law, developers can use the StoreKit External Purchase Entitlement. This entitlement allows apps distributed on the App Store solely in South Korea the ability to provide an alternative in-app payment processing option. Developers who want to continue using Apple’s in-app purchase system may do so and no further action is needed.

At the same time, Apple says some features will not work if developers opt to use a different payment method:

The Telecommunications Business Act in South Korea was recently amended to mandate that apps distributed by app market operators in South Korea be allowed to offer an alternative payment processing option within their apps. To comply with this law, developers can use the StoreKit External Purchase Entitlement. This entitlement allows apps distributed on the App Store solely in South Korea the ability to provide an alternative in-app payment processing option. Developers who want to continue using Apple’s in-app purchase system may do so and no further action is needed.

Other jurisdictions have been increasingly working to pry open Apple’s grip on the App Store, but South Korea has managed to make the most progress so far. It’s a safe bet it won’t be the last.