US-based technology giant Apple recently announced new rules for its App Store which could have a major impact on online gambling operators—particularly the ones that offer online sports betting and online casino to its iOS users.

As per the new guidelines, every app that offers real-money gaming activities must be built in Apple’s native iOS code instead of relying on embedded HTML5 code.

HTML5 comprises various technologies used to build rich web applications. Building on top of the classic HTML markup language used for decades to build websites, it adds modern APIs—including access to the file system, OS notifications, offline support, geolocation and more—that allows for rich development that can go beyond the web.

For that reason, it has become a common tool for developers looking to build an app that supports multiple operating systems. While apps will be compiled to native executable code, they may act as a “wrapper” for an HTML5 website: This is often cheaper to build, easier to maintain, and faster to deploy code simultaneously across multiple platforms, including iOS and Android.

The new policy applies specifically to all “real money gaming” operators that offer online poker, casino, sports betting, and prohibits this using such HTML5 wrappers. On June 3, Apple issued updates to the App Store Review Guidelines that read:

HTML5 games distributed in apps may not provide access to real money gaming, lotteries, or charitable donations, and may not support digital commerce. This functionality is only appropriate for code that’s embedded in the binary and can be reviewed by Apple.

The revised policy is already in place for new apps or apps that are awaiting approval from the tech giant. Existing apps have been given three months deadline to be in compliance: By September 3, 2019 all gambling apps must be built natively rather than as HTML container apps.

Customers with real-money apps already installed on their iOS devices will continue to be able to use them even after the deadline. However, Apple won’t approve future updates.

Google’s App Store for Android devices, Google Play, does not permit real money gambling apps at all (though this policy is slowly changing, with a trial in UK, Ireland and France). But Android devices allow for apps to be installed out-of-store, a process known as “sideloading.” Online gambling operators thus offer Android apps via direct download, with no restrictions.

Apple, on the other hand, has always allowed real money gambling in its App Store, though strictly in regulated markets only. However, Apple does not allow out-of-store installation—the only way to download an app is through its App Store—so all operators must adhere to the rules.