These exploits, however, have been completely removed on iOS 14. With JIT, the source code is translated into the machine’s native code in real time.Īpple has never offered official support for JIT compilation on iOS, but some developers have found ways to run it with hacks, which came with the cost of having several bugs and low performance. JIT, or Just-In-Time compilation, is a way to run software that will be compiled during its execution, while a traditional software is fully compiled before it is executed. But first, let me briefly explain what JIT is and how it works on iOS. Riley Testut, the developer behind AltStore, shared with 9to5Mac more details about how this change will impact these unofficial apps that offer console and virtual machine emulation. Apple has silently introduced support for Just-In-Time (JIT) compilation on iOS 14.2, which will allow emulation apps to run at full speed on the iPhone and iPad. These apps run based on hacks and exploits, which reduces performance considerably - but that’s about to change. You may know some unofficial iOS apps that offer some kind of emulation.