Converting Web Apps to Mobile: How Expo's Dom Components Make it Easier Than Ever
We hear it from our clients all the time. They want to meet their customers wherever they’re at and they know that a mobile app can be a great part of that story. The thing is, mobile apps can be complicated to write, and sometimes hard to rationalize when you’ve already got a working product on the web.
Fortunately, with a new feature from Expo called DOM Components, it’s never been easier to reuse your web code in mobile and gradually adopt native features. The result is a faster path to publishing on the app stores without compromising the experience that mobile users expect.
This article will explore the business-level and user-experience benefits to incremental adoption and take a high-level look at how Expo’s DOM Components work to support this.
What Are Expo’s DOM Components?
Expo’s DOM Components are a recent addition (introduced around SDK 52) that allow you to embed web components directly in a React Native app. By adding a special directive ("use dom") at the top of a component file, you tell Expo to render that component using React DOM (web) instead of the usual native elements.
Under the hood, Expo dynamically bundles that component as a “mini website” and displays it in the app, with all the same settings and defaults as the rest of your Expo project. This means you can take an existing piece of your web app UI (like a complex chart or form) and have it running inside a mobile app with minimal changes.
It’s essentially “Web within Native” – giving you a shortcut to get your web UI into a mobile app while you incrementally replace or enhance it with truly native components over time.
Why Do I Need a Mobile App?
One of the biggest benefits to launching a mobile app is access to the app store ecosystems. Having an app on the Apple App Store and Google Play opens up a whole new channel for users to discover your app. This also means a gain in credibility and brand presence.
Having your app icon appear on the user's home screen keeps your product in sight on a daily basis. In fact, studies show that mobile users spend ~88% of their device time on apps versus only 12% on mobile sites. Having a mobile app means that you will be able to tap into this preference and get your users to re-engage with your product without losing them to another browser tab.
Beyond discoverability, we find that mobile apps naturally encourage more frequent use. The convenience of a dedicated app (through things like quick launches, saved logins, offline storage, etc) means the friction to quickly check in on the product is much lower than it is for a website.
All of these factors lead to improved user retention. From a business perspective, higher engagement and retention can translate to better customer lifetime value and more opportunities to monetize or provide value to your users.
Leveraging Native Device Capabilities for a Better UX
Another big advantage of native apps is the ability to leverage device hardware and APIs to deliver experiences that a web app can’t easily match.
Mobile apps can use features like the camera, GPS, accelerometer, contact list, and more. This opens the door to functionality like scanning QR codes, uploading photos, using geolocation-aware features, augmented reality, or fitness tracking – enriching your app’s user experience.
While some of these can be attempted in web apps, the native implementations are often smoother and more reliable. For instance, accessing the camera via a native module will feel more seamless to the user than a web camera prompt.
By converting your app with Expo, you can gradually incorporate these native features as needed without overhauling your whole codebase on day one.
Expo offers a suite of pre-built APIs (for camera, location, haptics, sensors, etc.) that you can integrate once you have your basic app running. In fact, Expo’s DOM Components approach encourages an incremental enhancement model: your web functionality continues to work inside the app, and whenever you’re ready, you can swap a web component for a truly native one to use a device capability.
For example, you might initially reuse a web image upload form in the mobile app, but later replace it with a native image picker that taps directly into the phone’s camera roll – providing a more familiar experience for mobile users. This ability to progressively enhance the app’s capabilities means you can deliver immediate value and then wow users with new features over time, all while using the same overall codebase.
One Codebase, Less Overhead (Unified Development)
From a development strategy standpoint, using Expo’s DOM Components to convert your web app into a mobile app offers significant efficiency gains. You get to maintain a single codebase for both web and mobile platforms, which is a huge win for small teams and startups. Changes made to shared components can reflect in both the website and the app, ensuring consistency across platforms and reducing duplicate work.
This unified development approach cuts down on maintenance cost – you don’t have to fix bugs in two separate codebases or implement new features twice. It also means your team (or you, if you’re a solo dev) can focus on one set of technologies (primarily JavaScript/TypeScript and React) to deliver for all platforms.
Expo is built on React Native, so under the hood the mobile app uses native UI components for performance. The magic with DOM Components is that it allows you to mix in React DOM (web) components when needed, so you can reuse complex UI parts from your web app immediately. Over time, as you refine the mobile experience, you might replace those web-based bits with fully native implementations, but you get to choose the pace.
The ability to share a codebase and gradually refine it not only saves engineering effort, it also ensures your branding, design, and logic stay consistent for users on web and mobile (no more “the app is missing features that the website has,” or vice versa). For the audience familiar with coding, think of it as DRY (Don’t Repeat Yourself) applied to cross-platform development – Expo helps you avoid parallel development silos.
Faster Prototyping and Incremental Adoption
One of the biggest benefits to Expo’s DOM Components is the speed it takes to develop and iterate on a web conversion to mobile. Sometimes it means taking a project that would have typically taken you months and turns it into weeks. This type of rapid prototyping means that you’re quicker to test your idea and get it in front of your users and stakeholders for feedback without a major upfront investment. For a business, this agility can be a game-changer: you can get to market faster than competitors or adapt to user needs on the fly.
Equally important is the incremental migration capability. Traditional web-to-native rewrites often require a complete rebuild of the app in a new technology, which is time-consuming and risky (you might spend months before you know if it all works well).
Expo flips this script. With DOM Components, you’re not forced to rewrite everything at once. You can start by wrapping your whole web app in an Expo shell, get it running on mobile, and then identify which parts would benefit most from native optimizations. Maybe the web-based table works fine for now, but the image gallery would be smoother with native code – you can target that area specifically.
This approach lets you focus development effort where it matters most for mobile users, optimizing gradually. It also means you always have a working product at every step of the migration.
From a strategic standpoint, this reduces risk and allows for continuous delivery of improvements. You can release an initial app to users quickly, then seamlessly update it as you replace web components with native ones in subsequent versions. The result is a steadily improving mobile experience that aligns with your business priorities, without the “big bang” rebuild risks.
Key Takeaways
App Store Expansion: Converting your web app to a mobile app enables you to reach users on the Apple and Google app stores which expands your audience and boosts your visibility. An app on a user’s home screen also reinforces your brand presence.
Higher Engagement: Mobile apps tend to engage users more than mobile websites – people spend significantly more time in apps. Features like push notifications and offline access further improve retention by keeping users coming back, which can increase the value of your user base.
Native Device Features: A mobile app lets you leverage device capabilities (camera, GPS, sensors, etc.) to offer experiences that a web app can’t easily match. This can differentiate your product with better UX and open up new functionality (from AR features to simple conveniences like one-tap dialing or map directions).
Shared Codebase = Lower Cost: Expo’s DOM Components allow you to reuse your web code in a mobile app, meaning you maintain one codebase for both platforms. This leads to easier maintenance, consistency across web and mobile, and reduced development overhead since changes sync across both.
Faster Time-to-Market: Using Expo, you can prototype and launch a mobile app much faster by repurposing your existing web UI. You don’t have to hire separate iOS/Android developers or rebuild from scratch – a huge win for businesses that need to move quickly under tight budgets.
Incremental Improvement: With an Expo-based approach, you can incrementally migrate your web app to native. There’s no need for a risky all-or-nothing rebuild. You can roll out a functional app now and gradually enhance it with native components and optimizations, focusing on the areas that matter most for user experience.
Converting a web app into a mobile app is a strategic move to meet users where they are. Thanks to tools like Expo’s DOM Components, this move doesn’t have to be a monumental effort. It’s now possible to have the best of both worlds – the reach and familiarity of the web, and the engagement and capabilities of native apps – all within a unified project.
For coding enthusiasts and entrepreneurs alike, this means you can turn your web-based project into a pocket-sized mobile experience that delights users and drives business growth, without reinventing the wheel to get there.