Cross-Platform Development

One codebase, every platform.

React Native and Flutter apps sharing a single codebase across iOS, Android, and web — with native modules dropped in exactly where performance demands them.

One Shared Codebase

Around 85% of code written once, not twice.

Native Where It Counts

Native modules for the parts that genuinely need them.

Ship Both At Once

One release cycle instead of two teams and two dates.

60fps Or It Ships Again

Frame budgets enforced on real mid-range devices.

Scope Your App → See It On Each Platform

iOSAndroidWebTablet

1 codebase · 3 targets

release · v2.4.0● both stores

Shared bundle built41s

iOS archive signed2m 18s

Android AAB signed1m 52s

Uploading to both stores—

One App, Every Surface

The Same Codebase, Rendered Natively

Switch platform and watch the same screen adopt each system’s own conventions — iOS gets its typography and sheet behaviour, Android gets Material controls, web gets a pointer-first layout.

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Native on iOS, not a web view in a jacket

On iOS the app uses real UIKit primitives underneath — native navigation transitions, system sheets, haptics, and Dynamic Type. Users who have never heard of React Native cannot tell, which is the entire point.

SF Pro typography and Dynamic Type scaling respected throughout
Native navigation stack, so the swipe-back gesture behaves correctly
Haptics, Face ID, Apple Pay, and share sheets wired to the real APIs
Built and signed through Xcode, submitted like any native app

Swift interopUIKit bridgeTestFlightApp Store Connect

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Material conventions, not an iOS app in disguise

The most common cross-platform failure is shipping an iOS design to Android users. Buttons, dialogs, back-button behaviour, and typography all follow Material guidelines here, from the same shared codebase.

Material 3 components and the platform back-button contract honoured
Adaptive icons, themed splash, and edge-to-edge layout support
Tested across the mid-range devices your users actually own
Play Store bundles with per-ABI splits to keep download size down

Kotlin interopMaterial 3Play ConsoleAAB splits

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Layouts that use the space, not stretch to fill it

Tablets are where lazy cross-platform apps look worst — a phone layout scaled up with enormous whitespace. Responsive breakpoints in the shared codebase give tablets a genuine multi-column layout instead.

Breakpoint-driven layouts with master-detail on larger screens
Split-view and multitasking support on iPadOS
Keyboard shortcuts and external pointer support where relevant
Orientation handled properly rather than being locked to portrait

Responsive layoutSplit viewiPadOSFoldables

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The same components, running in the browser

React Native Web and Flutter Web let a large part of the same component tree render in a browser. It will not always be the right call — but where it fits, it is a third platform for a fraction of a third of the cost.

Shared component tree and business logic reused on the web target
Real URLs and routing, so pages are linkable and indexable
Progressive enhancement for browsers without the newest APIs
Honest assessment when a purpose-built web app would serve better

React Native WebFlutter WebPWASSR where needed

The Honest Split

How Much Code Is Actually Shared

“Write once, run anywhere” was always marketing. Here is what the split genuinely looks like on the apps we ship, by layer.

Shared architecture

Architecture

The 85% that should never be written twice.

Business rules, API clients, validation, state management, and formatting logic have no reason to exist in two languages. Duplicating them is how the iOS and Android versions of an app quietly drift apart until they behave differently for the same user.

One state layer and one API client, typed end to end
Validation and business rules defined once, so both platforms agree
A single design-token source driving both platforms’ styling
One test suite covering the logic that both apps depend on

React Native Or Flutter

Choosing Between The Two

Both are excellent and we build in both. The choice usually comes down to your existing team rather than a technical winner.

	React Native	Flutter
Language	TypeScript	Dart
Best if your team already knows	React / web	Nothing in particular
Rendering	Native platform components	Own rendering engine
Pixel-identical across platforms
Adopts platform conventions automatically
Web target maturity	Good	Improving
Easiest to hire for	Larger pool	Smaller pool
Typical bundle size	Smaller	Larger

Short version: if you have web engineers, React Native lets them contribute on day one. If you want the app to look identical everywhere and have no existing preference, Flutter’s rendering control makes that easier. Neither choice is one you will regret.

~85%Code shared

Weighted across a typical production app, measured not estimated.

2×Faster to market

Versus building and maintaining two separate native codebases.

60fpsFrame target

Enforced on mid-range Android hardware, not only flagships.

1Release cycle

One commit produces signed builds for both stores.

Native escape hatches

Performance

Native modules exactly where they earn it.

Cross-platform gets a bad reputation from teams who refused to drop to native when they should have. Heavy image processing, complex gestures, background location, and custom camera work belong in Swift and Kotlin — called from the shared codebase.

Native modules in Swift and Kotlin for genuinely heavy work
Gesture and animation work moved off the JS thread entirely
Frame timing profiled on mid-range Android, not just a flagship iPhone
Startup time budgeted and measured on every release

An Honest Framing

When Cross-Platform Is The Wrong Call

We build native apps too, and sometimes that is what we recommend. These are the cases where sharing a codebase costs more than it saves.

Go Fully Native When…

The platform itself is the product.

The app is graphics-heavy — games, AR, real-time video effects
It lives in deep OS integrations: widgets, watch, CarPlay, complications
You need day-one support for every new OS feature at announcement
You already have strong, separate iOS and Android teams
Only one platform matters and the other is not on the roadmap

Cross-Platform Wins When… most apps

The product is the same on both platforms.

Both platforms matter and the feature set is identical on each
The app is content, commerce, workflow, or data-driven
You want one team and one release cycle, not two of each
Time to market matters more than squeezing the last frame
The budget does not stretch to two native teams done properly

How We Build

From Scope To Both Stores

One track, not two. The platforms diverge only where they should.

Scope

Feature set, platform priorities, and the parts that will genuinely need native work identified up front.

Design Once

A design system with platform variants baked in, so iOS and Android differences are decided, not accidental.

Build Shared

Logic, state, and screens built once. Native modules written alongside where the profiler says they are needed.

Tune Per Platform

Frame timing, startup, and gesture feel tested on real devices at both ends of the price range.

Ship Together

One release train producing a signed iOS build and an Android bundle from the same commit.

Cross-platform is not about writing less code. It is about writing the same rule once, so both apps cannot disagree about what your product does.

Why we build this way

Shared Codebase

One React Native or Flutter codebase powering both iOS and Android, without a second team.

Single codebase across iOS and Android
Faster iteration than maintaining two apps
Native modules where performance demands it

2xFaster time to market

Native-Feel Performance

Smooth, native-feeling interactions, not the sluggish feel cross-platform apps are known for.

Native modules for performance-critical paths
Platform-specific UI where it matters
Tuned for smooth 60fps interactions

60fpsTarget performance

Lower Long-Term Cost

One team maintaining one codebase, instead of two teams maintaining two apps that drift apart.

One team, one codebase to maintain
Shared bug fixes and feature releases
Lower long-term maintenance overhead

40%Lower maintenance cost

Technology

What We Build With

Chosen per project, and always with a path back out if the decision needs revisiting.

React NativeFlutterTypeScriptDartExpoSwiftKotlinReanimatedReact NativeFlutterTypeScriptDartExpoSwiftKotlinReanimated

Redux ToolkitZustandTanStack QueryRiverpodBlocMMKVRealmSQLiteRedux ToolkitZustandTanStack QueryRiverpodBlocMMKVRealmSQLite

FastlaneEAS BuildFirebaseSentryDetoxMaestroCodePushApp CenterFastlaneEAS BuildFirebaseSentryDetoxMaestroCodePushApp Center

Questions

What Teams Ask About Going Cross-Platform

Usually asked by someone who has heard a cross-platform horror story.

Not if it is built properly, and that is a real condition rather than a reassurance. The tells that give cross-platform apps away are almost always avoidable: janky list scrolling, a back button that behaves wrongly on Android, iOS-style dialogs on Android, slow cold start, and animations that stutter under load. Each of those is a solvable engineering problem, and we treat them as release blockers rather than acceptable trade-offs.

For the overwhelming majority of apps — content, commerce, booking, workflow, social, dashboards — performance is indistinguishable from native when the app is built with attention to the JS thread and the render path. Where it genuinely differs is heavy graphics, sustained real-time processing, and complex custom gestures. Those get native modules, which is a normal part of the architecture rather than an admission of defeat.

Core platform APIs are usually available through the community ecosystem within weeks of release, and anything not yet wrapped can be bridged with a small native module in days. If your product depends on being first to adopt brand-new OS features every September, fully native is the more honest recommendation.

Yes — brownfield integration is well supported. New screens can be built in React Native or Flutter inside an existing native app, sharing navigation with the native parts. This is a common path for teams who want to test the approach on one feature before committing the whole product to it.

The business logic layer is the most valuable and most portable part of the codebase, and it moves across with far less pain than people expect. We also keep native modules genuinely modular so that a future migration replaces the UI layer rather than requiring a rewrite from nothing. It is a decision that stays reversible.

It depends mostly on your team. If you have React or web engineers, React Native means they contribute immediately and hiring is easier. If you have no existing preference and want pixel-identical rendering across platforms with tight control over the UI, Flutter is excellent. We build in both and will make a recommendation based on your situation rather than our comfort.

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