This article discusses the existing popular tools for mobile cross-platform application development. It is contrasted with the so – called native application development-when applications are created using the tools provided by the development companies of the respective platforms. Google provides a tool like Android Studio for its Android mobile operating system. The main programming languages used to create applications for this platform are Java and Kotlin. Apple, in turn, offers developers such an integrated development environment as XCode, in which development is carried out using the Swift programming language. The authors reviewed some of the most popular tools for cross-platform development, such as React Native, Xamarin and Flutter. React Native is a product developed by the company Facebook. It inherits the main technological aspects from another framework from Facebook-React. Programming here is conducted in the JavaScript language. React Native is suitable for web developers who have worked with React before and now want to try their hand at developing mobile applications. Xamarin is a framework supported by Microsoft. It provides tools for creating cross-platform applications for the iOS and Android mobile operating systems. This framework is bundled with Microsoft Visual Studio as a downloadable component. What is typical for a Microsoft product, here the C# programming language is used for development. This is a significant advantage of the Xamarin framework: during the creation of a mobile application, developers can use all the important and convenient features of this programming language. Flutter is a tool developed by Google to create apps for Android and iOS using a single code base. Unlike other popular solutions, Flutter is not a framework: it is a set of software development tools that contains everything you need to create cross-platform applications. It includes a visualization engine, ready-made widgets, and tools for working with the command line. The main programming language here is Dart. In the course of studying these tools, the authors made the following conclusions: tools for cross-platform development are an excellent solution if you need to create an application that does not require high performance: displaying information received from the server, simple local information processors, such as applications for social networks, online stores, organizer applications. These tools are not suitable for creating applications that require computing resources.