April 2025 Summaries

Kornel Kwiatkowski, a React Native developer at Pagepro, describes how they assisted a client in transitioning from maintaining two separate native apps for iOS and Android to a single cross-platform app using React Native and Expo. This migration addressed challenges such as delayed feature releases, bug accumulation, and increased costs due to the need for separate iOS and Android development teams. By adopting a modern tech stack that included React Native, Expo, and various supportive libraries, the development process became more efficient, enabling faster release cycles, reducing maintenance overhead, and lowering costs. The use of Expo facilitated development speed, allowed access to native features, and supported over-the-air updates, all of which contributed to a seamless app experience across platforms. The project resulted in a scalable app with consistent user experience and positioned the client for future growth by enabling more frequent experimentation and prototyping.

Beginning April 24, 2025, Apple mandates that all apps submitted to the App Store use Xcode 16 or later and be built with the iOS 18 SDK, meaning that any app built with a previous version will be rejected. Developers using Expo must ensure their apps are compatible by using SDKs 50, 51, 52, or 53, as these can be built with Xcode 16 or later, with SDK 52 or later defaulting to Xcode 16 automatically. Those using SDK 51 or earlier are advised to upgrade to SDK 52 or higher to comply with Apple's requirements. To build apps with Xcode 16 or later, developers should configure their build profiles to use an appropriate iOS server image, and they can refer to the supported Xcode versions by EAS Build to ensure compliance.

Expo native apps streamline performance by automatically handling multi-threading to optimize UI rendering, offloading business logic from the main/UI thread to background threads. JavaScript runs independently, ensuring smooth scrolling and gestures even if the JavaScript thread blocks. This approach mirrors techniques used by leading frontend teams to enhance user interactions. Debugging in React Native has improved, with Expo integrating Chrome DevTools for reliable JS-native debugging and performance optimization tools like React Scan. Expo recommends several optimization strategies, including using TypeScript, enabling ESLint, employing static JavaScript features, and utilizing the React compiler for automatic memoization to enhance app responsiveness. Additionally, leveraging advanced techniques like worklets for multi-threading in gesture-driven animations offers further performance boosts. Expo continues to support these optimizations through its tools and partnerships, helping developers maintain scalable and high-performing codebases.

In SDK 53, the New Architecture will be automatically enabled for all projects, aligning with React Native's default settings, although users can opt-out if desired. This marks a continuation from SDK 52, where it was introduced for new projects, and as of April 2025, 74.6% of projects have adopted it. The New Architecture supports new React and React Native features, such as Suspense and advanced styling, which are not available in the legacy system. While most transitions are expected to be straightforward, larger apps with outdated dependencies may require more effort. The legacy architecture may be phased out by late 2025, compelling a shift to the New Architecture for continued upgrades. Libraries such as react-native-reanimated and @shopify/flash-list will exclusively support the New Architecture in future versions, enhancing performance. Despite previous issues during migration, many have been resolved, though some libraries like @stripe/react-native still lack full support. Developers encountering migration obstacles are encouraged to report them on GitHub with reproducible examples, and temporarily disable problematic features while exploring other potential issues. The transition signifies a move towards universal adoption, with the legacy architecture potentially becoming a distant memory.

In the contemporary digital landscape, cross-platform voice agents are revolutionizing user interaction by providing seamless, human-like experiences across various devices and platforms such as iOS, Android, and the web. These agents facilitate diverse applications, from personal productivity assistants to customer support and language learning tools, all enhanced by ultra-realistic, multilingual voices. The development process involves creating an Expo project and configuring it with necessary dependencies, microphone permissions, and dynamic variables to ensure smooth operation across platforms. Developers can employ native client tools to extend functionality, and the voice agent's personality can be tailored using Large Language Models (LLMs) and system prompts. Looking forward, the evolution of voice agents is marked by advancements in context-aware conversations, multimodal interactions, and emotion-aware voice synthesis, promising more intuitive and empathetic user interfaces for industries like healthcare and education.

Solarin Johnson, a 17-year-old developer, shares his experience using EAS Hosting to deploy animated user interfaces built with Expo, highlighting its ease of use and efficiency. Johnson describes how EAS Hosting simplifies the deployment process for React Native web apps, drawing parallels to deploying Next.js apps with Vercel, and emphasizes the tool's minimal setup and rapid deployment capabilities. He outlines a project involving scroll-based animations powered by Reanimated and Expo Router, illustrating the user experience enhancements like scroll-linked progress bars and expandable flow bars. Johnson notes that deploying with EAS Hosting involves just a few simple CLI commands and eliminates the need for server or CDN configuration, making it an attractive option for both prototypes and production-ready apps. Additionally, he discusses optimizing Expo web apps for SEO and sharing, using Expo Router to add essential meta tags, and underscores the reliability and speed of EAS Hosting, which offers performance monitoring and tracks deployment history, asserting that it is becoming a preferred deployment solution within the evolving Expo ecosystem.

A tutorial on a 'Random Cat Generator' unexpectedly led the author to create a Pokémon-inspired project called PokéCatcher, which later evolved into a Player vs. Environment (PvE) game named PokeBattle Arena. Initially developed as a simple fetch-and-display app, a suggestion in the comments inspired the author to develop a turn-based battle system. Using tools like Grok and Replit, the author created a game where users select a Pokémon to battle against a randomly chosen opponent, with gameplay featuring animations, HP bars, and a combat log to track actions. The battles are simplified, with no complex elements like type weaknesses, and the player always attacks first. The app was built using Expo, allowing for real-time testing on mobile devices, and includes a rematch feature to restart battles quickly. The project, accessible on Replit, hints at future enhancements like type matchups and real-time player vs. player challenges, and credits PokéAPI for its indispensable role in providing Pokémon data.

Tyler Williams, an engineer at Infinite Red, discusses strategies to speed up the continuous integration and continuous deployment (CI/CD) process for React Native applications using Expo and EAS Workflows. The focus is on improving build times while maintaining high confidence in code quality, especially when running end-to-end tests. Williams suggests using EAS Workflows to fingerprint native builds, deploying JavaScript-only changes with EAS Update, and skipping native builds in CI when possible. By leveraging Expo's built-in features like fingerprinting and development builds, developers can significantly reduce the time it takes to run tests, from about 20 minutes to as little as 6 minutes per platform. This approach allows for more frequent testing on every pull request, increasing confidence in changes without slowing down the development process. However, there are tradeoffs, such as the development build not being entirely analogous to a release build, which may require additional testing setup for accuracy. Overall, these methods showcase the power of Expo's workflows in optimizing CI processes for React Native projects.

Jamie Barton, a seasoned software engineer, introduces Turso Offline Sync's integration with Expo applications, offering a more streamlined approach to developing local-first apps. By enhancing SQLite with bidirectional sync capabilities, this integration enables apps to function entirely offline, syncing data automatically when connectivity is restored, and provides native-speed database performance without the need for custom sync engines or backend infrastructure. Turso stands out with its per-user databases, allowing each user to have their own syncable data store across multiple devices, thus simplifying architecture by removing complex backend requirements. The solution is particularly beneficial for mobile-first apps, multi-device users, and offline-critical applications, and it is now available in public beta for experimentation and feedback, although it's not yet production-ready. Future enhancements, including automatic conflict resolution and sync protocol optimization, are in development to further improve the service.

Expo SDK 52 has introduced automatic fingerprinting for builds and updates, significantly enhancing compatibility between native code and the JavaScript bundle of an application. This feature is complemented by new CLI tools, eas fingerprint:generate and eas fingerprint:compare, which facilitate tracking changes in the native layer to prevent crashes due to mismatches. A fingerprint, a unique hash representing native dependencies, is automatically calculated during builds and updates, ensuring compatibility and preventing issues when JavaScript updates are incompatible with existing native binaries. The eas fingerprint:generate command allows developers to create and upload a fingerprint from their local project for easy access, while eas fingerprint:compare helps detect differences between builds or updates, simplifying debugging. These tools provide developers with increased insight and control over their app's native layer, reducing guesswork, improving stability, and enabling more confident updates, ensuring synchronization between JavaScript and native code and enhancing user experience.