Skip Framework Goes Open Source: SwiftUI for Android Becomes Reality

The cross-platform mobile development landscape has taken a significant turn with the announcement that Skip, a framework enabling iOS and Android app development from a single Swift/SwiftUI codebase, has gone completely open source after three years of development.

From Paid Tool to Open Source Solution

Prior to this announcement, Skip operated on a subscription-based model requiring license keys for app creation, with exceptions only for indie developers and free apps. This approach, according to the Skip team, helped bootstrap the product without outside investment. However, they acknowledged a fundamental truth about developer tools: "the plain truth is that developers expect to get their tools free of charge."

The decision to open source Skip wasn't purely about cost. The team identified a critical concern about tool durability that resonates with many developers. Building an entire app strategy on a small company's paid, closed-source tool carries risks: what happens if the company goes under, gets acquired and shut down, or discontinues the product? By going open source, Skip ensures that even if the current development team were to disappear, the solution would continue to exist, preserving developers' investments.

Bridging SwiftUI to Android

Skip's core innovation lies in bringing SwiftUI to Android by bridging it to Jetpack Compose. This approach allows iOS developers to write both their app's business logic and UI in the same codebase, with minimal additional effort. The framework represents a significant departure from traditional cross-platform solutions that often result in dated interfaces and weaker user experiences.

The Skip team argues that the rapid evolution of UI frameworks on both Android and iOS, with Material Expressive and Liquid Glass, has created a situation where using legacy cross-platform UI frameworks can lead to "dated interfaces, weaker user experiences, and real competitive disadvantages." By contrast, Skip enables fully native user experiences on both platforms.

Developer Experience and Limitations

Early adopters who used Skip during its paid phase have shared their experiences on Reddit. One user, jestecs, noted that "It is quite good there are some gotchyas here and there but overall it's been surprisingly pleasant to work with." Another user, JEHonYakuSha, provided more detailed feedback: "There are some issues where certain deprecated constructors are not supported so you may be used to an older way to defining your view modifiers or components, but once you get used to being a little creative and confirming what is supported, it is very good."

JEHonYakuSha also highlighted some practical considerations: developers can mix Kotlin code snippets into their Swift codebase using // SKIP INSERT comments, and only the Swift Package Manager is supported on the iOS side, which can make managing internal dependencies somewhat tricky.

One important caveat from Skip's documentation is that the framework is best suited for new projects or apps with few external dependencies. "Migrating an existing app to Skip is not trivial," the documentation warns. "Most apps contain many iOS-only dependencies that make an Android port challenging."

Technical Evolution and Ecosystem

Skip's journey began three years ago as a Swift-to-Kotlin transpiler and later added support for the most widely used SwiftUI APIs on Android. During this time, the team established the Swift Android Workgroup and released the Swift Android SDK, enabling natively compiling Swift code on Android.

Today, Skip supports many popular integration frameworks, interoperates with thousands of cross-platform Swift packages, and offers a comprehensive SwiftUI implementation. For developers seeking alternatives, SwiftCrossUI provides a SwiftUI-like API for UI across macOS, Linux, Windows, and some nascent support for Android.

The Skip framework is now available on GitHub, with all documentation, blog posts, and case studies moved to skip.dev. This open-source release positions Skip as a compelling option for developers looking to leverage their SwiftUI expertise across both major mobile platforms while maintaining native performance and user experience.

The move also aligns Skip with the broader trend of open-source development tools, joining Xcode, Android Studio, and other essential tools that are freely available to developers. As cross-platform development continues to evolve, Skip's open-source approach may help address some of the long-standing concerns about vendor lock-in and tool longevity that have plagued the space.