HomeServicesAppsCross-platform apps

One build for every phone.

We build apps with React Native and Expo that run on iPhone and Android from a single codebase, with native screens, native performance and faster updates.

Start a projectApps from £2,000
  • iPhone and Android
  • One shared codebase
  • Quick fixes after launch

Cross-platform stack

React NativeExpoExpo RouterTypeScriptEAS BuildEAS SubmitEAS UpdateSupabaseFirebaseRevenueCatSentry

Separate iPhone and Android apps mean two codebases to build, test and update every time something changes. We build one React Native codebase with Expo, adding native code only where a feature truly needs it.

Shared code, native feel.

React Native draws real native components on each platform, so one codebase still feels at home on iPhone and Android.

React Native and Expo

We use React Native with Expo and TypeScript, the setup React Native itself recommends for new apps, so tooling and upgrades stay well supported.

Platform-aware design

Shared logic with interfaces tuned per platform, such as Liquid Glass touches on iPhone and Material 3 patterns on Android, where the difference matters to users.

Native modules

When a feature needs device access beyond Expo's libraries, we write native modules in Swift and Kotlin with the Expo Modules API.

Cloud builds with EAS

EAS Build compiles signed iOS and Android builds in the cloud, and EAS Submit sends them to App Store Connect and Google Play Console.

Over-the-air updates

EAS Update delivers JavaScript fixes and small changes straight to installed apps, within store rules, without waiting for a full review.

Backend and data

We connect your app to Supabase or Firebase for accounts, data and storage, or to your existing systems through their APIs.

Done properly.

The details that decide whether cross-platform apps pays off.

Fixes that reach users quickly.

Small fixes ship through EAS Update, and larger releases go through the stores with phased rollouts. Every change is tested on real iPhones and Android phones first, and a developer reviews any code that AI helped write.

Update flow

TaskFix merged and reviewed
ReviewTest on both platforms
LaunchEAS Update rollout
ReportCrash check after release

When native code is the better choice.

Some apps need heavy graphics, complex background tasks or brand new platform features on day one. We tell you early if Swift or Kotlin would serve you better, and we can mix native screens into a React Native app.

Codebase at a glance

Shared code

Most app logic

Platform code

Where it helps

Languages

TypeScript, Swift, Kotlin

Updates

EAS and stores

How it works.

Clear steps, and you approve each one before we move on.

  1. 01

    Plan

    We decide what is shared, what is platform-specific and which native modules are needed.

  2. 02

    Design

    We design screens for both platforms and test a prototype on each.

  3. 03

    Build

    We build in React Native with Expo and share development builds as we go.

  4. 04

    Ship

    EAS submits to both stores, and later fixes go out as over-the-air updates.

Example project

A coffee subscription brand wanting iPhone and Android apps

Customers manage their coffee deliveries through a website that is awkward on phones. The brand wants an app on both stores for skipping deliveries, changing blends and getting dispatch alerts, without paying for two separate builds.

What we would do

  • Plan shared screens and platform-specific details
  • Build one Expo app in TypeScript
  • Connect subscriptions to the existing Shopify store
  • Ship fixes with EAS Update after launch

An illustration of how we would approach it, not a client result.

What you would get

  • One app on both stores
  • Dispatch alerts by push notification
  • Shared codebase with documentation
  • Cloud build and update setup
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Related work.

Projects where we did this kind of work.

Own product · iOS app

DisCam

A disposable-style film camera app, from name and icon to App Store listing.

Read the case study

Own product · iOS and Android app

RepCam AI

A fitness app that counts your reps through the camera, with challenges and daily drops.

Read the case study
More workSee everything we've built.Client projects and our own products, with what we did on each.See all work

Questions, answered.

Is React Native as good as a native app?

For most business apps, yes. React Native renders real native components, and Expo gives access to device features like the camera and notifications. For heavy graphics or very deep platform features, we may recommend Swift or Kotlin.

What are over-the-air updates?

They let us send JavaScript changes, like bug fixes and text tweaks, directly to installed apps through EAS Update. Larger changes and new native features still go through App Store and Google Play review.

Can you take over an existing React Native app?

Yes. We review the codebase, upgrade React Native and Expo where needed and fix urgent issues first. You get a short written plan before any larger changes begin.

How much does a cross-platform app cost?

Every app is quoted after a short call, with a fixed price agreed before we start. Building once for both platforms usually means less work than two separate native apps.

More in apps.

Every part of apps, run by the same team. See the overview

Apps

iOS appsBuilt to feel at home on iPhone.Explore iOS apps

Apps

Android appsMade for every Android phone.Explore Android apps

Apps

App designScreens that are easy to use.Explore App design

Apps

Subscriptions and paywallsIn-app payments ready at launch.Explore subscriptions and paywalls

Apps

Launch and ASOReady for review and discovery.Explore launch and ASO

Build once for both stores.

Tell us what you need. Charlie will come back with a plan and a price, usually within one working day.

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