SEOUL, South Korea — The Korea Media and Communications Commission, South Korea’s media and telecommunications regulator, fined Alphabet’s Google and Apple a combined 63.7 billion won ($47.6 million) on Wednesday over app-store payment and review practices. The commission said the companies “abused their dominance in app store markets by forcing local developers onto their own payment systems and by unfairly delaying app reviews.”

The penalties amounted to 42.9 billion won ($32 million) for Google and 20.8 billion won ($15.5 million) for Apple. In addition to the fines, the commission ordered both companies to let South Korean developers use external payment links within their apps and to improve their app-review procedures.

On payments, the commission said Google and Apple “unfairly pushed app developers toward their own in-app payment systems while barring payments through external websites.” The companies technically allowed third-party payment systems within their apps, according to the regulator.

The commission also said Google and Apple charged developers a 26% commission for those third-party payments and withheld some features available through the companies’ own systems. It said the arrangement effectively forced developers to use only the companies’ in-app payment systems.

The commission said it found instances in which Google and Apple delayed app reviews without clearly explaining to developers the reasons for the delays or when the reviews would resume. It also accused Apple of charging South Korean developers higher commissions than developers elsewhere from 2015 to January 2023.

Google and Apple did not immediately respond to requests for comment.

The South Korean regulator spent years investigating the U.S. technology companies for allegedly violating a 2021 law that prohibits app-store operators from forcing developers to use specified payment systems. Under the law, app-store operators cannot force developers to use their own in-app systems.

South Korea has for years closely scrutinized the business practices of foreign technology companies operating in its market. In 2021, South Korea became the first country to enforce a law prohibiting app-market operators such as Google and Apple from requiring developers to use their own in-app payment systems.