ContextThe most popular mobile platforms, Android and iOS, are traditionally developed using native programming languages—Java and Kotlin for Android, and Objective‐C followed by Swift for iOS, respectively. Due to their popularity, there is always a demand to convert applications written for one of these two platforms to another. Cross‐platform mobile development is widely used as a solution where an application is written once and deployed on multiple platforms written in several other programming languages. One common cross‐platform approach that has been used recently by some research groups is the Trans‐Compilation approach. They focus on translating a program written in iOS into Android or vice versa. The main problem with their solutions is that library function mapping is not generalized and usually functions constitute most of the parts of any program.ObjectiveThis study aims to introduce an automatic library mapping approach for mobile programming languages.MethodA library function of a source language will be automatically mapped to a corresponding function of the destination language by using the function structure for the two languages. The function structure includes the library to which the function belongs, the return type, parameter types, and the number of parameters. To test our approach, we map from Swift to Java.ResultsThe results of our experiments show that our automatic library mapping approach achieves an average accuracy of 83.6% when tested on the most used libraries and outperforms current state‐of‐the‐art mapping techniques in terms of mapping accuracy.ConclusionThese findings show that our automatic mapping approach is promising and can help to overcome the limitations of the trans‐compilation approaches.