Why is DolphiniOS's Wii and GameCube emulator not coming to the App Store?

DolphiniOS, a fork of the popular Dolphin emulator for Nintendo Wii and GameCube games, has confirmed that it is not coming to the Apple App Store, even though emulators are now supported. In a post on Friday, the developer behind the emulator says this is because Apple does not allow DolphinOS to use its built-in performance-boosting technology.

As explained by developer OatmealDome, DolphinOS – along with other Wii and GameCube emulators – uses something called Just-In-Time (JIT). This is a compiler that "translates" the GameCube and Wii's PowerPC-based code into a language that other devices can understand, making emulation run more smoothly.

But as oatmealdom notes, Apple doesn't allow third-party apps to use JIT compilers. "The only exceptions are Safari and alternative web browsers in Europe," the developer writes. "We submitted a DMA [Digital Markets Act] interoperability request to Apple for JIT support, but Apple rejected the request a few weeks ago."

Although there is a way to avoid JIT by using an "interpreter", oatmealdom writes that it is "several times slower than a JIT compiler." A pair of videos shared by OatmealDome show how poorly the Mario Kart Wii emulation performs on the iPhone 15 when using the interpreter instead of the JIT. The Verge contacted Apple with a request for more information about JIT-related rules, but did not immediately receive a response.

Since Apple loosened its policies on retro game emulators earlier this month, we've already seen game emulator Delta top the App Store charts. More are likely to come - provided they aren't removed first.