All services
Pillar 11 · Mobile

React Native App Development Services

What you get

Capabilities included in every engagement.

  • React Native 0.74+ with New Architecture
  • JSI, Fabric, TurboModules
  • Expo (EAS Build + Update)
  • Hermes engine
  • Reanimated 3 (UI-thread animations)
  • FlashList for large lists
  • TanStack Query + Zustand
  • React Navigation
  • Native module fork-and-patch
  • CodePush / Expo Updates (OTA)
The stack we default to

What we use. Why we pick it.

We useWhy we pick it
React Native 0.74+ (New Architecture)JSI removes the bridge serialization tax on hot paths. Fabric gives synchronous layout. TurboModules replace lazy-loading hacks. The architecture we default to on new builds.
Expo (managed + bare workflow)Expo managed covers 95% of apps. When you need native code, expo prebuild gives you the iOS and Android projects checked in while keeping EAS Build and EAS Update. Bare-from-day-one is rarely the right call.
Hermes engineSmaller bundles, faster cold starts, predictable memory. Default on RN 0.70+ for a reason.
Reanimated 3Gesture-driven animation runs on the UI thread. No JavaScript-bridge jank on a SectionList scroll.
TanStack Query + ZustandServer state separated from client state. Cache, retry, refetch-on-focus in TanStack Query. Cross-screen client state in Zustand. Redux only on projects that already use it.
TypeScript strictEvery network response and reducer has a type. The 'undefined is not an object' runtime crash is gone.
FlashList over FlatListLower memory, fewer re-renders, better scroll performance on lists over 50 items. Default on new builds.
EAS Update / CodePush (OTA)Ship a JS-only fix in an hour instead of three days through App Store review. Targeted rollouts by version and channel. Shipped OTA across clients for five years without App Store pushback.
Sentry + Datadog RUMReal-device crash and performance data. Not 'works on my simulator'.
Reference architecture

How it fits together.

React Native with Expo EAS handles OTA updates; the app talks to a typed backend over authenticated requests, no build queue when a button changes.

Client React Native Expo · Hermes Reanimated · TanStack Query Delivery Expo EAS · OTA Ship JS without a store review Service FastAPI Pydantic · async Python JWT · push webhooks Data Postgres Typed migrations Redis cache · S3 media OTA pull HTTP SQL

When React Native wins certain builds

Your engineering team already writes React on the web. Hooks, patterns, types, tooling all carry across. A developer switching from a Next.js codebase is productive on day one. A Flutter engineer, however strong, is not - they have a new language, new state libraries, new test runner, new debugger to learn. That is the single biggest reason we pick RN over Flutter for a team that is already JavaScript-native.

The other reason is OTA. Expo Updates and CodePush let you ship a JavaScript fix in under an hour. Flutter has no first-class equivalent. For fintech, live commerce, or any app where a broken copy change blocks revenue for three days on Apple’s review queue, that difference matters.

When to pick something else

  • iOS-only with a small team - native Swift and SwiftUI ships faster.
  • 120Hz animation-heavy UI - Flutter’s Impeller is closer to native than React Native yet.
  • AR or 3D experience - use ARKit or SceneKit on iOS, ARCore on Android.
  • Team of two web engineers, one designer, 14 weeks to iOS and Android - React Native is the honest answer.

We tell you which one you are before we quote the job.

Our React Native capabilities

  • New Architecture (JSI, Fabric, TurboModules) on new builds. Synchronous calls across the bridge, no serialization tax on hot paths.
  • Expo managed + bare workflows - managed first, bare when native code is unavoidable.
  • Native module bridging - we write Swift and Kotlin when a library does not exist or is broken. Fork, patch, vendor, cut an upstream PR.
  • Shared logic with React web - hooks, types, validation, API clients shared across mobile and web.
  • OTA deployment - EAS Update or CodePush. Version-gated, channel-targeted, Sentry-watched.
  • Hermes tuning - smaller bundles, faster startup, predictable memory.
  • Reanimated 3 for anything gesture-driven. UI thread, not JS thread.
  • FlashList over FlatList for lists over 50 items.
  • Type-safe backend contracts - OpenAPI generated TypeScript clients from FastAPI or Pydantic.

Case studies

  • Cross-border airtime and prepaid electricity top-ups in 5 seconds - React Native consumer app, React web + reseller dashboard, shared FastAPI backend. 130+ operators in 44 countries via DT One aggregator. Webhook-driven order state machine hits a ~5-second top-up SLA. Multi-gateway payments (Stripe, PayPal) settled into one ledger.
  • Live auction bidding without the timer drifting - React Native buyer app, React operator console, FastAPI REST + WebSocket backend. Server-authoritative 30-second countdown, atomic bids with seen-current-highest conflict check, OneSignal for auction-start alerts, AWS S3 for vehicle galleries.

How we work on a React Native engagement

Week 1 - architecture. Screen list, navigation graph, API contract, state boundaries. Expo managed vs bare decision, OTA strategy, crash-report SDK picked. Written down before any JSX.

Weeks 2 to 3 - the spine. Auth, first real data fetch, first navigation, first animation. TestFlight build by Friday of week 2. If it does not run on a real iPhone and a real Android device by then, we regroup.

Weeks 4 to 10 - features, one per week. Demoed on real hardware, not a simulator. Flamegraphs cut before merge when we touch a hot path.

Weeks 11 to 12 - polish and release. Accessibility, dark mode, analytics, crash reporting, App Store and Play Store staged rollouts.

OTA updates - the operational lever most agencies underprice

OTA is not a party trick. On the apps where it matters, it changes operations:

  • Fix a broken copy change in 30 minutes, not 3 days.
  • Turn off a feature flag from EAS without a redeploy.
  • Roll out a new pricing page to 10% of users, measure conversion, push to 100%.

Getting OTA right needs discipline: version gates (do not push JS that requires a native change), rollback runbooks, and Sentry watching every update. We ship OTA as standard, not as a nice-to-have.

Native modules - what happens when a library breaks

Every React Native project hits a moment when a dependency is broken. BLE stops advertising on Android 14. A camera library leaks memory on older iPhones. Expo’s Bluetooth plugin misses a permission on iOS 17.

We fork, patch, vendor, and cut the upstream PR. The project never stops. The patch lives in the repo with a note explaining why - so the next engineer knows.

Backend coupling - typed end to end

React Native apps we build talk to a FastAPI backend. Request and response schemas are Pydantic on the server, mirrored as TypeScript on the client via a shared OpenAPI spec. The “backend sent a field the app did not expect” class of bug disappears. See Backend Development.

Hermes, Reanimated, Fabric - the tuning we do by default

  • Hermes on from day one. Smaller bundles, faster cold starts.
  • Reanimated 3 for anything gesture-driven. UI thread so scrolling does not stall behind JavaScript.
  • Fabric / TurboModules for new builds. Synchronous calls across the bridge, no serialization tax on hot paths.
  • FlashList over FlatList for anything over 50 items. Lower memory, fewer re-renders.

Why teams pick our React Native delivery

If your engineering team already lives in React and TypeScript, the ramp-up we need is short. Hooks, types, and patterns move across the web and the mobile app on day one instead of day ninety.

OTA is in by default: version gates, Sentry watching, rollback runbook in the repo. We have been shipping JavaScript fixes in under an hour across clients for five years without App Store pushback. And when a library is broken (it will be - that is RN), we fork and patch in your repo. Waiting on a maintainer is not a plan.

Senior engineers on the product, full IP transfer at launch (source, CI, infrastructure, all yours), and the option for us to stay on retainer after go-live if you want that.

FAQ

Questions people ask before we start.

When the team already writes React for the web - sharing hooks, types, and patterns between RN and a Next.js app cuts onboarding in half. When Expo OTA updates matter to operations (fintech, live commerce, time-sensitive ops). When JavaScript-first libraries (e.g. a specific payment SDK or AWS Amplify) are load-bearing.

Heavy animation or 120Hz UI commitments - Flutter's Impeller wins. AR or 3D rendering - use native. Teams with no React experience - adopting RN and React together is a double hire-and-train.

Expo managed for almost every build. When you need deep native code (CarPlay, advanced Bluetooth, a custom camera pipeline), expo prebuild gives you native projects checked in while keeping EAS Build and Update. Bare-from-day-one is rarely the right call.

Apple permits JavaScript-based updates as long as you are not changing the app's core purpose. Bug fixes, copy changes, new features that do not reshape the app are fine. We have shipped OTA updates across clients for five years without pushback.

For list-heavy, animation-heavy apps: yes. Hermes + Reanimated + Fabric close the gap. For 3D rendering or computer vision: use the platform. Pick the tool for the workload, not the brand.

We fork, patch, vendor, and cut an upstream PR. Every major RN engagement has a moment when a library's bug blocks you - usually a permission flow or a background task. We fix the library, keep moving, and document why in the repo. Waiting on maintainers is not a plan.

Yes. New projects start on the New Architecture. Legacy migrations we do project-by-project once the library landscape catches up. We do not flip the switch for sport.

Start a react native app development services engagement

Tell us what you’re building.

Name the product and the platforms. We reply with an RN-or-Flutter recommendation, a timeline, and a scoped proposal for a discovery sprint. NDA signed on request. Response within 1 business day.

The team on the call

Named engineers, not a pool.

You speak to the person who’ll review the architecture. No account-manager layer. No offshore switcheroo.

Founder & Lead Engineer

Sameer Donga

Shipping Flutter, FastAPI, and AI systems since 2019. Reviews the architecture on every engagement.