Measuring While Playing Fair: An Empirical Analysis of Language and Framework Usage in the iOS App Store

Reverse engineering research has mainly focused on binaries compiled from C and C++, however, in the iOS ecosystem, neither of these languages are the focus of application developers. Apple provides their own languages with Objective-C and Swift as the official choices, while third party cross-platform frameworks, like Microsoft’s.NET MAUI, Jetpack Compose, Flutter or even React Native promise unified development across iOS and Android. To investigate the relevance of languages for R&D efforts in software understanding, we conduct a historical analysis spanning 84,432 distinct iOS applications over the past five years.
Unlike previous approaches, we sidestep the technical and legal challenges of the FairPlay DRM system used to encrypt iOS apps and demonstrate that FairPlay does not cover various useful metadata, some of which can be used to detect the presence of programming languages in individual binaries and applications. Our key findings show that, as expected, Swift is now included in almost every popular application, however without phasing out Objective-C usage. Additionally, newer cross-platform languages like Flutter and Kotlin have seen a steady increase in use, while.NET has stagnated since 2020. All of these applications still include and interact with Objective-C, demonstrating that cross-language analysis is now an unavoidable challenge in the modern iOS analysis landscape.