TouchHLE

touchHLE is a free and open-source emulator for iOS applications, originally developed by an anonymous programmer going by the pseudonym hikari_no_yume. It is written in Rust to work specifically with games developed for older iOS versions, and as of version 0.2.3 it supports hundreds of games.

touchHLE was first released in February 2023 where it was able to run Super Monkey Ball, a launch title for the App Store in 2008 which was at the time considered "long lost" due to it being incompatible with newer iOS versions. Support for other games, such as the Lite version of Super Monkey Ball, Crash Bandicoot Nitro Kart 3D and Touch & Go was added in later builds, and the emulator was ported to Android after a pull request was issued to add support for it, allowing Android devices to run legacy iOS games.

The emulator makes use of high-level emulation where touchHLE itself takes the place of iOS and provides its own implementations of operating system frameworks, thus avoiding any dependency on copyrighted Apple firmware and libraries; the only code executed by the emulated CPU is the app binary and open-source libraries from Apple. hikari_no_yume also stated that they do not plan on supporting newer versions of iOS both on a technical and philosophical standpoint, citing the complexity of implementing 64-bit iOS apps and system libraries and changing trends in the mobile app ecosystem where the emergence of free-to-play games brought about concerns regarding the perceived decline in quality of mobile games.