Apple blocks PC emulator from being available in iOS App Store and third-party app stores

App Review has rejected a submission from the developers of UTM, a generic PC system emulator for iPhone and iPad.

The open source app was submitted to the store, given the recent rule change that allows retro game console emulators, like Delta or Folium. App Review rejected UTM, deciding that a “PC is not a console”. What is more surprising, is the fact that UTM says that Apple is also blocking the app from being listed in third-party app stores in the EU.

As written in the App Review Guidelines, Rule 4.7 covers “mini apps, mini games, streaming games, chatbots, plug-ins and game emulators”.

UTM says Apple refused to notarize the app because of the violation of rule 4.7, as that is included in Notarization Review Guidelines. However, the App Review Guidelines page disagrees. It does not annotate rule 4.7 as being part of the Notarization Review Guidelines. Indeed, if you select the “Show Notarization Review Guidelines Only” toggle, rule 4.7 is greyed out as not being applicable.

It’s therefore unclear if the Apple reviewers for UTM were incorrect in asserting the application was not suitable for distribution by third-party app stores in the EU.

However, as it stands, UTM is not proceeding to contest the ruling. As apps distributed on iOS cannot use a JIT compiler (other than specially entitled alternative browser engines), the functionality and performance of the emulators running through UTM SE, the version submitted for review that had JIT disabled, was significantly impaired. UTM says getting UTM SE approved “isn’t worth fighting for”.

UTM for iOS will continue to be available using older ‘grey market’ sideloading methods for open source software, such as compiling and installing the app manually via Xcode. UTM for Mac is available in the Mac App Store.

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