How To Build Cross-Platform Mobile Apps?

How To Build Cross-Platform Mobile Apps?

Let this blog article guide you through the daunting question of how to build cross-platform mobile apps properly from both technical and organisational points of view. You will learn about popular frameworks, development environments, UI building, app logic implementation, deployment, and performance optimisation.

Introduction To Cross-Platform Development

Many businesses face the dilemma of choosing between fast, cost-effective cross-platform development and native development focused on superb functionality and performance. Building cross-platform apps for both iOS and Android allows you to reach a broader customer base. Using the same codebase on both platforms, the development team can complete the project faster, shortening the time to market. Moreover, the core functionality and user interface are consistent across all platforms. If those considerations are of prime importance for your business, then a cross-platform approach is the right choice.

How To Build Cross-Platform Mobile Apps?

Any mobile app development services starts with selecting an appropriate tech stack. In designing a cross-platform application, the starting point lies in picking a proper framework.

Choosing the Right Cross-Platform Framework

Two leading frameworks have gained widespread popularity thanks to their ease of use and robust performance: React Native and Flutter. We will provide all the further comparisons based on these two libraries.

React Native

Facebook-developed React Native is an open-source framework that lets engineers build mobile apps using JavaScript and React. It offers a rich set of components and libraries, enabling visually appealing and interactive user interfaces. Moreover, React Native's "write once, run anywhere" approach saves time and effort as developers can reuse code across different platforms.


Backed by Google, Flutter has quickly become a favourite among developers for its fast development cycles and expressive UI. It uses Dart, a modern programming language, and provides a set of customisable widgets to build stunning interfaces. Flutter's hot reload feature allows developers to view changes instantly, reducing development time significantly.

Setting Up the Development Environment

Once you've chosen a cross-platform framework while seeking the means how to build cross-platform mobile apps, setting up the development environment is the next step. Whether you opt for React Native or Flutter, ensure your development team has the necessary tools and dependencies installed. Both frameworks offer comprehensive documentation and command-line tools that streamline the setup process.

Building User Interfaces with Cross-Platform Frameworks

Cross-platform frameworks make it relatively easy to design visually appealing UIs that adapt seamlessly to different screen sizes and resolutions.

React Native UI Development

React Native's component-based architecture simplifies UI development. You can choose from various pre-built components or create custom ones to suit your app's unique requirements. Styling and layout are also managed using CSS-like style sheets, enabling developers to achieve consistent designs across platforms.

Flutter UI Development

Flutter's UI development revolves around widgets, which are the building blocks of its interfaces. It provides an extensive collection that can be customised to create stunning designs. Flutter's "widgets within widgets" approach allows for limitless possibilities when it comes to UI design.

Implementing App Logic and Functionality

Both React Native and Flutter offer features and libraries that facilitate the seamless integration of app logic.

React Native App Logic

As React Native leverages JavaScript, your development team can tap into a vast ecosystem of libraries and packages to implement various functionalities. Whether handling user input, making API calls, or managing state, JavaScript provides flexibility for app logic.

Flutter App Logic

Being a modern and feature-rich language, Dart enables developers to write clean and efficient code for app logic implementation. Flutter's reactive style programming allows for a responsive user experience, and its robust typing system helps catch errors during development.

Deploying and Publishing Cross-Platform Apps

Publishing your app on app stores requires overcoming a few technology-related issues and some legal nuances. Let’s first focus on technical perfection.

React Native App Deployment

For React Native apps, you must bundle the JavaScript code and assets before submitting them to app stores. The process may vary slightly between iOS and Android, but React Native's documentation provides clear guidelines for both platforms.

Flutter App Deployment

Flutter simplifies the deployment process with its "flutter build" command. This command generates the necessary app bundles for iOS and Android. With the bundles ready, you can follow the respective app store guidelines to publish your app.

App store-related concerns

Having resolved platform-specific issues and version compatibility nuances, take into account the app store’s (both Google Play and Apple App Store) guidelines and app approval time. Both marketplaces have strict guidelines and review processes for app submissions, as well as review the app submissions within a different timeline (it ranges from a few days to several weeks).

Performance Optimization for Cross-Platform Apps

One common concern with cross-platform apps is performance. While React Native and Flutter provide efficient performance out of the box, there are still a few best practices that can further optimise your app's speed and responsiveness.

Optimising React Native Apps

Use native modules and avoid excessive JavaScript bridge calls for computationally intensive tasks. Additionally, utilise React Native's InteractionManager API to prioritise essential tasks and improve the user experience.

Optimising Flutter Apps

Leverage Flutter's native code compilation and hardware-accelerated graphics to enhance performance. Keep UI rendering smooth by minimising the number of unnecessary widgets and avoiding heavy computations on the main thread.

Successful Cross-Platform Apps and Their Development Stories

If still in doubt, check out the cross-platform development cases to get a complete understanding of both React Native and Flutter dynamics, as well as overall paint a picture of what shape will your upcoming solution’s SDLC take. The answer to how to build cross-platform mobile apps will probably become more explicit.


A renowned financial news and information platform ventured into cross-platform development using Xamarin. They built native-like apps for iOS and Android platforms, ensuring an optimised user experience. Xamarin's code-sharing capabilities and seamless integration with Visual Studio, a widely used development environment, helped Bloomberg streamline their development process and maintain feature parity between their apps on different platforms. The Bloomberg app has become a valuable resource for financial professionals, providing real-time market data, news, and analysis.


This global online marketplace for lodging and tourism experiences is a remarkable example of a successful cross-platform app. To ensure broad accessibility and reach, Airbnb opted for a cross-platform approach using React Native. By choosing this framework, they leveraged their existing web development team's expertise in JavaScript, harnessing faster development and easier code sharing between their web and mobile platforms. The result was a seamless and consistent user experience on iOS and Android devices.

Discuss Upcoming Trends and Advancements With Our Experts

Wondering how to build cross-platform mobile apps can be the start of an exciting and rewarding journey. With the right framework, development environment, and performance optimisation, you can create apps that resonate with users across different platforms - especially if travelling with a responsible software development partner by your side.

Whether adopting new cross-platform technologies or integrating emerging features, consulting with experts can give your app a competitive edge. Our software development company UK market knows as S-PRO will be happy to provide a team of seasoned professionals skillful at any type of mobile development. Drop us a line to get a consultation and discuss your idea: you can be positive we will find the most suitable solution for your business needs.


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